Britain will begin renewing its nuclear weapons system after the Government won a key vote in the Commons last night.

Tony Blair shrugged off a mass revolt of Labour MPs - involving three from Sussex - to secure a majority of 248 votes in favour of developing a new generation of submarines capable of firing Trident D5 missiles.

Mr Blair said replacing Trident was "essential for our security in an uncertain world".

But 161 MPs voted against the Government's motion.

And 167, including 94 Labour backbenchers, supported a rebel amendment opposing an "early decision"

and saying the case for replacing Trident was "not yet proven".

The rebels included David Lepper (Brighton Pavilion), Des Turner (Brighton Kemptown) and Michael Foster (Hastings and Rye).

The county's two other Labour MPs - Laura Moffatt (Crawley) and Celia Barlow (Hove and Portslade) - toed the party line and backed renewal.

Mr Lepper, who first joined CND in 1961 and has met survivors of the Hiroshima bomb, said it was "morally, strategically and financially" a mistake for the UK to have nuclear weapons.

He said the estimated £20 billion cost would be better spent on other priorities, including better equipment for conventional troops.

The Labour rebels were joined by Norman Baker, Liberal Democrat MP for Lewes. But Mr Blair's victory was assured after Tory leader David Cameron ordered his MPs to back Trident.

Mr Cameron said replacing Britain's nuclear deterrent was in the national interest and a decision had to be taken now.

Experts say the existing Trident system will last another 17 years.

But Mr Blair said it would take about 17 years to develop and build a replacement.

The UK currently deploys 16 Trident missiles on each of its four Vanguard-class submarines.

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