Shadow defence minister Kevan Jones has said it is "absolutely right and necessary" for the UK to retain an independent nuclear deterrent, but it must take into account the costs involved.
World events demonstrate that in an unpredictable era our country needs the ultimate security guarantee.
The precise nature of the deterrent must be judged on meeting military capability requirements and cost.
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In other words, the Prime Minister will say that leaving the EU would not lead to a single EU law being abolished instantly.
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