For Labour, shadow defence minister Kevan Jones said it was "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," he said.
"The precise nature of the deterrent must be judged on meeting military capability requirements and cost."
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Staying blustery for the next 24 hours with strong winds driving some rain, sleet and snow from west to east tonight.
The mother of murdered Boris Nemstov's girlfriend is worried her daughter is being treated as if she had something to do with the killing.
Student Charlie Mann was jailed for 16 months for the attack on his mother at their family home while high on Meow Meow.