THE Tories were accused yesterday of seeking to drag the vital issue of Trident replacement down to the level of gutter politics.

Defence Secretary Michael Fallon faced a backlash after he accused Labour leader Ed Miliband of planning to “stab the United Kingdom in the back” over the renewal of Britain’s nuclear weapons.

Mr Fallon claimed that Labour would have to abandon any plans to renew the Trident fleet in order to secure the support of the Scottish National Party (SNP) in a hung parliament.

In the latest in a series of increasingly personal attacks on Mr Miliband by senior Tories, Mr Fallon said: “Ed Miliband stabbed his own brother in the back to become Labour leader.

Now he is willing to stab the United Kingdom in the back to become prime minister.

”The row broke out as Labour prepared to sign off its election manifesto at a Clause Five meeting of the shadow cabinet together with senior members of the national executive, the national policy forum and the Parliamentary Labour Party.

Labour — along with the Tories — has committed itself to replacing the ageing cold-war fleet of Vanguard-class submarines which carry the Trident missiles, and maintaining the continuous at-sea deterrent, ensuring there is always one nuclear-armed vessel on patrol.

Mr Miliband accused Mr Fallon of demeaning himself and his position with his underhand attack.

“Our clear position is four boats, because that’s what the experts say. The Conservatives are trying to create division with us where there is not division,” he said.

“Michael Fallon is a decent man, but today I think he has demeaned himself and demeaned his office. 

“National security is too important to play politics with. I will never compromise our national security, I will never negotiate away our national security.”

SNP leader Nicola Sturgeon said her party had made clear that it saw Trident as a “fundamental issue.”

She said: “We would never be in any deal with a Labour government who is going to renew Trident and we would never vote for the renewal of Trident or for anything that facilitated that renewal.”

CND general secretary Kate Hudson accused the Tories of “running scared from a serious debate about defence.”

She said: “Senior military figures warn that the £100 billion white elephant of Trident replacement does nothing to keep us safe and is resulting in thousands of jobs in the armed forces being slashed.

“How a blind commitment to squandering our overstretched national resources on a cold-war weapon can be touted as being ‘strong on defence’ is beyond me.”

CND said its survey of more than 700 parliamentary candidates from the main political parties showed more than 80 per cent would vote against Trident replacement, including 75 per cent of Labour candidates. 

“It’s time for the Conservatives and Labour to wake up to the huge public opposition to Trident,” Ms Hudson said.