Select Committee on Foreign Affairs Minutes of Evidence

Memorandum by Professor Christopher Greenwood, CMG, QC



  1.  This memorandum reviews, in summary form, the international law arguments regarding possible military action against Iraq. It does not deal with considerations of United Kingdom domestic law. While I am aware that a draft Security Council resolution is currently under discussion in New York, this memorandum was prepared without my having seen that draft.

  2.  For the reasons set out in this memorandum, I believe that military action against Iraq might be justified (depending on the evidence of Iraq's weaponry and intentions) on the following grounds:—

    (1)  if the UN Security Council adopts a fresh resolution authorizing military action against Iraq and any conditions set out in that resolution are met; or

    (2)  under existing Security Council resolutions on the basis that the Security Council considered that (a) Iraq is in material breach of those resolutions and (b) that breach constitutes a threat to international peace and security in the Gulf area. This would not require a fresh Security Council authorization of military action; or

    (3)  under the right of self-defence if an armed attack by Iraq against the United Kingdom or one of its allies was reasonably believed to be imminent. This would not require any action by the Security Council.

  In my opinion, international law would not permit recourse to force against Iraq on the basis that the United Kingdom and its allies were still engaged in a "war" dating back to 1990-91 (a different argument from (2) above), on the basis of any theory based on the notion of a "war against terrorism" or on the basis of a "doctrine of pre-emption". I have set out my reasoning on all of these points below.


  3.  The possibility of military action in 2002 has to be seen in the context of the actions taken by the UN Security Council and by a number of States, including the United Kingdom in the aftermath of the Iraqi invasion of Kuwait in 1990. That invasion, which was a flagrant violation of international law, was condemned by the Security Council in Resolution 660 (1990), which required Iraq to withdraw from Kuwait. In common with most of the subsequent resolutions on Iraq, this resolution was adopted under Chapter VII of the UN Charter and its provisions were therefore legally binding on Iraq.

  4.  When Iraq ignored the requirement that it withdraw, the Security Council adopted a series of further resolutions, including Resolution 678 (1990) by which the Council—

    "Authorizes Member States co-operating with the Govt of Kuwait, unless Iraq on or before 15 January 1991 fully implements, as set forth in para 1 above, the above-mentioned resolutions, to use all necessary means to uphold and implement resolution 660 (1990) and all subsequent relevant resolutions and to restore international peace and security in the area." (Emphasis added)

  The reference to "all necessary means" was clearly understood to be an authorization of military action. The passage emphasised shows that that authorization was not limited to the liberation of Kuwait but included an authority to use all necessary means for the purpose of restoring peace and security in the area.

  5.  Following the end of the fighting in March 1991, the Council adopted Resolution 687 (1991). That resolution referred to all of the earlier resolutions on Iraq, including 678. In paragraph 1 the Council—

    "Affirms all thirteen resolutions noted above, except as expressly changed below to achieve the goals of the present resolution, including a formal ceasefire." (Emphasis added)

  Resolution 687 did not repeal Resolution 678. That resolution remained in force to the extent that one of its objectives, namely the restoration of international peace and security in the area had not yet been achieved.

  6.  Resolution 687 then laid down what the Council considered Iraq had to do in order to ensure the restoration of international peace and security in the area. The Council required that Iraq—

    "unconditionally accept the destruction, removal, or rendering harmless, under international supervision, of:

    (a)  all chemical and biological weapons and all stocks of agents and all related subsystems and components and all research, development, support and manufacturing facilities related thereto;

    (b)  all ballistic missiles with a range greater than one hundred and fifty kilometres, and related major parts and repair and production facilities." (Paragraph 8)

  7.  In addition, paragraph 12 required Iraq—

    "not to acquire or develop nuclear weapons or nuclear weapon usable material or any subsystems or components or any research, development, support or manufacturing facilities related to the above."

  8.  As a means to achieving this partial disarmament, Resolution 687 also required Iraq to submit to intrusive weapons inspection initially by UNSCOM and the IAEA. The details of this requirement were set out in Resolution 715 (1991). Other provisions of Resolution 687 required Iraq not to commit or support any act of terrorism and not to permit any terrorist organization to operate from its territory (paragraph 32).

  9.  Iraq formally accepted these requirements but Resolution 687 is legally binding because of Chapter VII of the UN Charter, not because of Iraq's acceptance of it; it is not the equivalent of an agreement.

  10.  Iraq has never complied with these ceasefire conditions and has repeatedly been found to be in breach of the requirements of Resolution 687 regarding international peace and security. See, for example, Resolutions 949 (1994), 1060 (1996), 1115 (1997) and 1137 (1997). In 1998 the UN Secretary-General drew up a Memorandum of Understanding with Iraq regarding weapons inspections. The Security Council then, in Resolution 1154—

    "stresses that compliance by the Government of Iraq with its obligations, repeated again in the Memorandum of Understanding, to accord immediate, unconditional and unrestricted access to the Special Commission and the IAEA in conformity with the relevant resolutions is necessary for the implementation of Resolution 687 (1991), but that any violation would have the severest consequences for Iraq."

  11.  In fact, Iraq continued to violate its obligations; see, eg, Resolution 1205 (1998). After yet another attempt to resume inspections, UNSCOM reported to the Security Council on 15 December 1998 that—

    "As is evident from this report, Iraq did not provide the full co-operation it promised on 14th November 1998.

    "In addition, during the period under review, Iraq initiated new forms of restrictions upon the Commission's work. Amongst the Commission's many concerns about this retrograde step is what such further restrictions might mean for the effectiveness of long-term monitoring activities.

    "In spite of the opportunity presented by the circumstances of the last month, including the prospect of a comprehensive review, Iraq's conduct ensured that no progress was able to be made in either the fields of disarmament or accounting for its prohibited weapons programmes.

    "Finally, in the light of this experience, that is, the absence of full cooperation by Iraq, it must regrettably be recorded against [sic] that the Commission is not able to conduct the substantive disarmament work mandated to it by the Security Council and, thus, to give the assurances it requires with respect to Iraq's prohibited weapons programmes." (UN Doc. S/1998/1172, pp. 7-8)

  12.  This report was followed by the withdrawal of the UNSCOM inspectors and US/UK military action (Operation Desert Fox).

  13.  SCR 1284 (1999) replaced UNSCOM with UNMOVIC and required that Iraq allow UNMOVIC unrestricted access. Iraq, however, has refused—until September 2002—to permit UNMOVIC to operate within Iraq.


  14.  There is no doubt that the Security Council has the authority under Chapter VII of the UN Charter to adopt a fresh resolution authorizing military action against Iraq. Chapter VII gives the Security Council that power if it determines that there is a threat to international peace and security (Article 39) and that military action is necessary to deal with that threat (Article 42). The Council has already determined, in Resolution 687 (1991), that the removal of certain types of weapon from Iraq is necessary for the restoration of peace and security and that, to date, Iraq has not complied with its obligations in that regard.

  15.  In my opinion, it is clear that military action taken in accordance with a fresh mandate from the Security Council would be lawful. Like all military operations, it would, of course, have to be conducted in accordance with the Geneva Conventions, 1949, and other applicable rules of international humanitarian law.


  16.  Nevertheless, I do not believe that a new resolution expressly authorizing military action is necessary as a matter of international law. In my opinion, the authorization to use "all necessary means" contained in Resolution 678 (1990) (quoted in paragraph 4, above) has not been terminated by the Security Council. The imposition of a ceasefire by Resolution 687 (1991) suspended hostilities and thus suspended the authority to use force but Resolution 687 reaffirmed Resolution 678 (see paragraph 5, above) and thus left open the possibility of further military action to achieve the objectives of Resolution 678 in the event of Iraqi violation of the ceasefire terms.

  17.  Contrary to what is frequently suggested, Resolution 678 was not solely about the liberation of Kuwait and the authorization to the coalition to use force went beyond the goal of liberating Kuwait and authorized military action for the purpose of restoring international peace and security in the area. Resolution 687 (1991) then determined that the restoration of international peace and security required the partial disarmament of Iraq and (separately) its renunciation of any involvement in or support for terrorism. Resolution 687, paragraph 1 affirmed Resolution 678 except to the extent that the other provisions of Resolution 687 expressly changed Resolution 678. The text of Resolution 687 contains nothing which expressly (or impliedly) indicates that the Council either considered that the mandate contained in Resolution 678 had been discharged or that it could not be relied upon in the event of Iraq continuing to pose a threat to international peace and security.

  18.  It is, of course, true that Resolution 678 is now nearly twelve years old and was almost certainly not intended to remain in force indefinitely. But the fact that it is still relevant today is due solely to Iraq's persistent violation of its obligations under Resolution 687. The effect of some of those violations (primarily those in respect of disarmament) is that the threat to international peace and security which Iraq posed in 1990-91 has continued until the present day.

  19.  On that basis, it is open to the Security Council to determine that Iraq continues to be in breach of the ceasefire conditions in Resolution 687 and that that breach involves a threat to international peace and security which peaceful means have failed to resolve. The effect of such a determination would be that the authorization of military action in Resolution 678 would again be rendered active. That would not necessarily require a Security Council resolution. It could be done by means of a Presidential Statement (which would require a consensus in the Council). Moreover, a resolution stipulating that Iraq must take certain steps by a prescribed date could (depending on its wording) mean that the Council was determining that failure by Iraq to take such steps was a breach threatening international peace and security.


  20.  Article 51 of the UN Charter provides that—

    "Nothing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security. Measures taken by members in the exercise of this right shall be immediately reported to the Security Council and shall not in any way affect the authority and responsibility of the Security Council under the present Charter to take at any time such action as it deems necessary to maintain or restore international peace and security."

  It was in the exercise of this right that the United Kingdom took military action in Afghanistan in October 2001.

  21.  The question is whether the right of self-defence under customary international law which is preserved by Article 51 of the Charter would justify military action against Iraq on the basis of a threat of armed attack. In my opinion, it would do so if the threat was of an imminent armed attack but not otherwise.

  22.  Although Article 51 refers to the right of self-defence "if an armed attack occurs", the United Kingdom has consistently maintained that the right of self-defence also applies where an armed attack has not yet take place but is imminent. A large number of other governments (including those of the USA, France, other NATO States and the former USSR) have espoused this view. It also has strong support from commentators. Thus, Judge Rosalyn Higgins (writing before her election to the International Court of Justice) has said that—

    ". . . in a nuclear age, common sense cannot require one to interpret an ambiguous provision in a text in a way that requires a state passively to accept its fate before it can defend itself. And, even in the face of conventional warfare, this would also seem the only realistic interpretation of the contemporary right of self-defence. It is the potentially devastating consequences of prohibiting self-defence unless an armed attack has already occurred that leads one to prefer this interpretation—although it has to be said that, as a matter of simple construction of the words alone, another conclusion might be reached." (Problems and Process (1994), p. 242)

  The same view has been taken by Sir Humphrey Waldock (81 RC (1952-II) 496-8), Judge Schwebel (136 RC (1972-II) 478-83), Sir Gerald Fitzmaurice (92 RC (1957-II) 171), Sir Robert Jennings and Sir Arthur Watts (Oppenheim's International Law, 9th ed., 1992, vol. I, p. 421) and Sir Derek Bowett (Self-Defence in International Law (1958) 187-92). Waldock, Schwebel and Jennings are all past Presidents of the International Court of Justice.

  23.  I accept that other writers, notably Professor Ian Brownlie (International Law and the Use of Force by States (1963) 257-61), have taken the contrary view but, with great respect to them, I believe that the view expressed by Judge Higgins and the other writers quoted above accords better with State practice and with the realities of modern military conditions.

  24.  Nevertheless, the right of anticipatory self-defence is quite narrowly defined. Ever since the United Kingdom-US exchange in what has become known as the Caroline case in 1837-38, the right has been confined to instances where the threat of armed attack was imminent. In my opinion, that still reflects international law and, in so far as talk of a doctrine of "pre-emption" is intended to refer to a broader right to respond to threats which might materialise some time in the future, I believe that such a doctrine has no basis in law.

  25.  In assessing what constitutes an imminent threat, however, I believe that it is necessary to take account of two factors which did not exist at the time of the Caroline. The first is the gravity of the threat; the threat posed by a nuclear weapon or a biological or chemical weapon used against a city is so horrific that it is in a different league from the threats posed by cross-border raids by men armed only with rifles (as in the Caroline). The second consideration is the method of delivery of the threat. It is far more difficult to determine the time scale within which a threat of attack by terrorist means, for example, would materialise than it is with threats posed by, for example, regular armoured forces. These would be material considerations in assessing whether Iraq posed an imminent threat to the United Kingdom or its allies.

  26.  If Iraq did pose such an immediate threat then, in my opinion, military action against Iraq for the purpose of dealing with that threat would be lawful. The degree of force used would have to be proportionate to the threat and no more than necessary to deal with that threat (including preventing a recurrence of the threat). In addition, the use of force would have to comply with the separate requirements of the Geneva Conventions and other applicable rules of international humanitarian law.


  27.  In my opinion, the other legal grounds which have sometimes been advanced in discussion as a basis for military action against Iraq are unconvincing.

  28.  The suggestion that, because Iraq has violated the terms of the ceasefire embodied in Resolution 687 (1991), any of the coalition States which were engaged in the hostilities of 1990-91 would be justified in resuming hostilities seems to me to be based on a pre-1945 view of international law which cannot prevail against the clear language of the UN Charter. Violation of a ceasefire does not in itself justify reversion to military action today unless the original legal basis for the use of force remains in place. Accordingly, the United Kingdom might be entitled to resort to military action on the basis of Resolution 678 (1990), under the conditions set out above. It does not have an automatic right to resume belligerency simply because it was a party to the 1990-91 hostilities and Iraq has violated the ceasefire.

  29.  Nor, in my opinion, do references to a "war against terrorism" provide a basis for renewed military action against Iraq. If there were evidence of close Iraqi involvement in terrorism and a threat of imminent terrorist attack supported by Iraq, then that would justify military action by way of self-defence and, in certain circumstances, under Resolutions 678 (1990) and 687 (1991) (see paragraph 8, above). But the concept of a "war against terrorism", even if it has any international legal content at all, is, in my view, far too vague to serve as a basis for legal action where the criteria for self-defence are not met.

  30.  Finally, references to "regime change" do not, in my opinion, furnish a free-standing justification for military action. It is possible that the only way of achieving international peace and security might be to change the government of Iraq. Likewise, if action were taken in self-defence, there are circumstances in which self-defence might justify imposing a change of government (if that were the only way of removing the threat of armed attack from Iraq). However, the nature of the Iraqi regime does not, in my opinion, furnish a legal justification for military action in and of itself.


  31.  Accordingly, my conclusion is that military action against Iraq would be justified if:—

    (1)  The Security Council gave a fresh authorization to use force and military action was taken in accordance with that resolution; or

    (2)  The Security Council indicated that Iraq was in material breach of Resolution 687 (1991) and that breach entailed a threat to international peace and security, in which case action would be justified within the framework of Resolution 678 (1990); or

    (3)  Iraq posed a threat of an imminent armed attack against the United Kingdom or its allies and military action could therefore be taken under the right of self-defence.

Christopher Greenwood, CMG, QC

24 October 2002

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