EMILY THORNBERRY stuck to her guns in the increasingly fractious debate over Trident renewal yesterday after being barracked by hawkish Labour MPs.

The shadow defence secretary was repeatedly heckled during her defence review presentation at Monday night’s meeting of the Parliamentary Labour Party.

She argued that the party was not facing a binary choice between “Trident or nothing” but should consider other security options.

Ms Thornberry faced such vocal hostility from some Labour MPs and peers that at one point she was forced to tell them: “There’s no point trying to shout me down.”

Former shadow defence minister Kevan Jones was among the MPs who briefed the press after the meeting, branding her performance “waffly and incoherent, cringeworthy.”

Giving her record of events on Radio 4’s Today programme yesterday, Ms Thornberry said a handful of Trident enthusiasts had “kicked off” at the meeting, but they were not representative of the party as a whole.

She also warned that technology being developed by Russia, China and the US that would allow Trident nuclear submarines to be detected could render the weapons system obsolete.

“If we are being left behind by technology, if there is a possibility of cyber attack, if there is the development of drones, then actually these nuclear deterrents may not in fact be nuclear deterrents and that is the issue we need to debate,” Ms Thornberry argued.

The tensions on display at the meeting may have contributed to a decision to postpone the debate on Trident that was scheduled to take place at yesterday’s meeting of the shadow cabinet.

Shadow home secretary Andy Burnham admitted that it may be “impossible” to reconcile the differences of opinion on the issue.

In a coded appeal for Labour MPs to be given a free vote on Trident renewal, he said: “The party needs to find some way of accommodating that and allowing people to move forward and actually move on to other issues and hold the government to account.”