Select Committee on Defence Eleventh Special Report

ANNEX: Initial MoD response to the Defence Select Committee's Report: "The Future of the UK's Strategic Nuclear Deterrent: The White Paper"

Conclusion 7. Why are decisions required now on participation in the Trident D5 life extension programme?

Conclusion 28. What are the total costs of UK participation in the Trident D5 life extension programme?

Conclusion 32. What are the effects, financial or otherwise, of the exchange of letters between the Prime Minister and the US President agreeing UK participation in the Trident D5 life extension programme before the parliamentary vote?

There has been no formal commitment by the UK to the Trident life extension programme but it would have been incoherent to ask Parliament to endorse the decision to procure replacement submarines unless we had received an assurance from the US that we could participate in the life extension programme. That was the intention behind the inclusion of this issue in the exchange of letters between the Prime Minister and the US President.

Subject to Parliament endorsing our decision, we intend that this will be a joint programme with the United States. We need to maintain this joint approach in order to achieve best value for money. The intention is to refurbish the whole stockpile of Trident D5 missiles by around 2020. In order to achieve this, we need to commit this year to the procurement of some long-lead items for the life extension programme.

We plan that life extended Trident D5 missiles will be brought into service on the Vanguard-class submarines towards the end of their lives. Participation in the life extension programme is important to enable us to maintain the existing deterrent in service until the end of its planned operational life.

The total costs to the UK of participation in the Trident D5 life extension programme will be around £250M. These costs are in addition to the standard annual running costs for the Trident D5 missile are included in the calculation of the overall running costs of the deterrent.

As the White paper indicated at paragraph 2-5, we do not believe that further procurement of Trident D5 missiles will be necessary through that missile's planned in-service life. The exchange of letters between the Prime Minister and President makes clear that one of the options for the future is jointly to investigate the possibility of a further programme to extend the life of the Trident D5 missile beyond the early 2040s to match the life of the new class of submarines that we now plan to procure. The possible costs, and technical feasibility, of a further life extension programme are currently unknown.

Conclusion 11. How does the Government determine what constitutes a minimum deterrent?

Conclusion 10. What is the operational significance of the reduction in the number of UK nuclear warheads?

The White Paper made clear that we are committed to retaining only the minimum capability necessary to deter potential aggressors. The process by which we make an assessment of our minimum deterrent requirements is described in paragraph 4-9 of the White Paper. We make an assessment of the minimum destructive capability that we need to be able to deliver in order to outweigh the potential benefits a potential aggressor might believe they would derive from an attack on our vital interests. This includes an assessment of the decision-making processes of future potential aggressors and of defensive measures that a potential adversary might employ in an effort to reduce the impact of the UK's nuclear capability.

We are not prepared to release precise details of this assessment process because of the sensitive nature of the analysis involved and to maintain ambiguity over the circumstances in which we might consider use of our nuclear deterrent.

We have made clear that we will reduce the number of operationally available warheads from fewer than 200 to fewer than 160 in the course of this year. The significance of that is that we will have reduced our number of operationally available warheads by 20% and will then dismantle these warheads.

We believe that, by any measure, dismantling around 40 nuclear warheads demonstrates our continuing commitment to reduce where possible our nuclear deterrent capabilities and to set an example to other countries who hold nuclear weapons to do likewise. It represents a further important step towards our goal of a world in which there is no place for nuclear weapons.

We have also reduced the number of warheads deployed on our single submarine on deterrent patrol. The Strategic Defence Review announced a reduction from 96 to 48 warheads and we made clear in the White Paper that 48 is now the upper limit on warhead numbers rather than necessarily the actual number deployed.

Conclusion 13. The Government should be clearer that ambiguity over the potential use of the UK deterrent does not lead to a lowering of the threshold for nuclear use.

We are absolutely clear that there has not been any reduction in the threshold at which we might contemplate use of our nuclear deterrent. As we have made clear repeatedly, we would only ever contemplate use in self defence (including the defence of our NATO allies), and even then only in extreme circumstances.

Conclusion 12. The Government should do more to explain what the concept of deterrence means in today's strategic environment.

The Defence Secretary covered this ground in more detail than in the White Paper in his speech at Kings College London earlier this year. He said:

There are some who …. argue that it is not the threat but the concept of deterrence which is somehow outdated and no longer relevant in a post-cold-war world.

I do not accept this. I think it is unfortunate that the idea of deterrence has become so closely identified with the cold war. In its simplest terms, deterrence is about dissuading a potential adversary from carrying out a particular act because of the consequences of your likely retaliation. This is not an especially complex or unique concept. Nor does it have anything inherently to do with nuclear weapons, or superpower blocs. Our conventional forces are themselves a form of deterrent; they can and do deter various different kinds of states and non-state actors even in today's post-cold-war world.

The reality is that it is hard to be sure exactly what capability will deter any particular threat. The best we can do is aim to retain a broad spectrum of capabilities to enable us to respond to a range of potential threats. But there is a strong argument that nuclear weapons are unique in terms of their destructive power, and as such, only nuclear weapons can deter nuclear threats.

Paragraphs 3-6 to 3-12 of the White Paper describe the range of future risks and challenges the Government has considered in taking decisions on the future of the Trident system, and the possible role we see for the UK's nuclear deterrent in managing these potential future threats.

Conclusion 14. How does a reduced yield differ from a sub-strategic role? Why was a sub-strategic role thought necessary in 1998 but is no longer required?

Conclusion 15. How does this square with NATO nuclear doctrine?

UK nuclear doctrine matches that of NATO. The UK's nuclear weapons remain committed to the defence of NATO as before and we will continue to participate fully in all aspects of NATO nuclear policy and planning.

Ever since the Trident system came into service, we have had some flexibility in the scale of any use of our nuclear deterrent. This flexibility stems from an ability to vary the number of missiles and warheads which might be used and the ability to employ a reduced yield from our nuclear warhead. We plan to retain this flexibility. We would not want any potential aggressor to judge that they could act with impunity towards the UK because they felt that we would be unwilling to deploy the maximum destructive effect possible with the Trident system. Any legitimate use of nuclear weapons would be in response to extreme circumstances but, having a degree of flexibility in the potential scale of its use makes our deterrent more credible against the range of nuclear threats we may face in the future.

What has changed is the way in which we describe this capability and this is where we currently differ slightly from NATO terminology. We have previously described it as a sub-strategic capability. But we have decided to cease using this term for the simple reason that we believe any use of our deterrent will be strategic in intent and in effect.

Conclusion 20. The Government should set out a stronger narrative on the forward commitment of the Government to achieve nuclear non-proliferation.

The Defence Secretary also set out the position in detail during his evidence session with the Committee on 6 February:

Q386 Robert Key: Secretary of State, the United Kingdom is a signatory to the Non-Proliferation Treaty and the White Paper says that we are fully compliant with all our NPT obligations, and the White Paper goes on, "Nevertheless, we will continue to press for multilateral negotiations towards mutual balance and verifiable reductions in nuclear weapons". What is the Government currently doing to press for those multilateral negotiations?

Des Browne: Mr Key, we not only say that; we actually set out in some detail in a fact sheet and an annex to the White Paper itself how we address our international legal obligations and particularly the nuclear Non-Proliferation Treaty, so there is no need for me to read that. In summary, and we have set out in the White Paper what we have done over the last ten years in dismantling our maritime tactical nuclear capability and the RAF's WE177 bomb, reduced the maximum number of operational warheads, and our ambition is to reduce that further, and ceased production of fissile material for nuclear weapons. We have in my view, and I think this has been recognised even in evidence before this Committee, a good record in living up to our international obligations in this regard. For the future, we continue to support and we have made progress in 13 practical steps towards the implementation of Article VI agreed in 2000; we have ratified the Comprehensive Nuclear Test Ban Treaty; we have increased our transparency by publishing historical accounting records of our defence fissile material holdings; we have pursued a widely welcomed programme to develop expertise in methods and technologies that could be used to verify nuclear disarmament; we have produced a series of working papers culminating in a presentation to the 2005 NPT Review Conference and, looking to the future, our priority remains to press for negotiations in the Conference on Disarmament of the Fissile Material Cut-Off Treaty; we welcome the draft text which the United States tabled last year; we are also concerned whether to accept the very broad mandate proposed and agree to open negotiations towards a treaty without delay, and we are also actively engaged in the global initiative to combat nuclear terrorism but we will be playing a key and active role in shaping and contributing to the forward-looking programme of this important new development. That is all to be read in the context of what we have already put into the public domain with the White Paper and in the accompanying fact sheet.

The key point to note is that any route to a world free from nuclear weapons must be a gradual and carefully managed process, taken forward incrementally and verifiably, ensuring we maintain balance, stability and security as we move forward. Implicit in this is the fact that this is a multilateral process and so we must also bring along our allies, friends and other interlocutors throughout the process. We see the negotiation of a Fissile Material Cut-off Treaty as the next logical phase for multilateral nuclear disarmament. This would be a positive step forward and is one we are pursuing energetically.

On 22 February, FCO Minister of State Dr Kim Howells gave a speech at the Conference on Disarmament reiterating the UK's commitment to the principles and practice of multinational nuclear disarmament and encouraging the multilateral community to rise to the challenges of nuclear disarmament. A copy of the speech is available on the FCO website.

Conclusion 22. The Government should set out in more detail what were the comparative advantages of cost, range, operation and invulnerability associated with cruise and D5 missiles.

This point was covered in detail in the information sent to the Committee on 31 January, in which we said:

As for the option of cruise missiles launched from submarines, we are clear that, in both cost and capability terms, retaining the Trident D5 missile is by far the best approach. A comparison between cruise and ballistic missiles is set out in detail in Box 5-1 of the White Paper.

An option based on submarine-launched cruise missiles would, like the option we have decided on, require the procurement of new nuclear-powered submarines to fulfil the deterrent role, as the existing conventional role submarine flotilla, and the Astute class which will replace them, are required to undertake other key defence tasks. Indeed, given that a much larger number of cruise missiles, compared to Trident D5 missiles, would be required to meet our minimum deterrence requirements, moving to a deterrent based on submarine-launched cruise missiles could well lead to a requirement for additional submarine hulls.

Because of the costs and capability disadvantages of cruise missiles set out in the White Paper, we have not undertaken a detailed analysis of what the requirement for submarine hulls would be.

It is also the case that moving to a submarine-based cruise missile solution would necessitate the procurement of new nuclear-capable cruise missiles and also the development of a new nuclear warhead suitable for use with a cruise missile, both at considerable cost and technical risk. Thus, such an option would have significant disadvantages in both cost and capability terms compared with the option we have chosen.

Conclusion 25. The Government should make it clear when it will be in a position to give more accurate cost estimates and what work needs to be done to extend the life of the Vanguard class by 5 years.

In evidence to the Committee on 6 February, we estimated that the total costs for the 4-boat fleet of the planned life extension programme would be in the hundreds of millions of pounds. We will provide more detailed information to the Committee on the work required and the associated costs as it becomes available.

Conclusion 33. Why could the UK not re-manufacture warheads to the existing design?

As the White Paper makes clear, decisions on whether to refurbish or replace the existing warhead are likely to be necessary in the next Parliament. The refurbishment option would require the re-manufacture of a number of warheads to the existing design, employing a combination of new and recycled components. There will be a range of factors that determine whether or not we decide to produce a warhead to a new design, including cost and our ability to certify the warhead stockpile in terms of safety and reliability. We will provide more information to the Committee as it becomes available.

9 March 2007

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