Emily Thornberry has acknowledged some Labour MPs "kicked off" at her during Monday evening's meeting of the Parliamentary Labour Party as she updated them on the progress of her defence policy review.
But the shadow defence secretary told BBC Radio 4's Today programme this morning she did not think her critics represented all Labour backbenchers.
Earlier this morning shadow home secretary Andy Burnham said it would likely be "impossible" for the pro-Trident and anti-Trident sides of the Labour Party to reach an agreement.
Thornberry, like Jeremy Corbyn, is opposed to the renewal of Britain's nuclear weapons system. Many Labour MPs are in favour and several shadow cabinet ministers have hinted they would quit if Labour ditches its support for the renewal of Trident.
Former Labour security minister and Royal Navy chief Lord West phoned in to the Today programme during Thornberry's interview to dismiss her argument as "nonsense".
Speaking to the BBC, Thornberry repeated her claim made at the PLP meeting that the Trident nuclear submarine fleet could be made obsolete by drones. She had suggested Trident could become as outdated as World War II Spitfires.
"The idea of the Trident replacement is that it can hide in the sea. If technology is moving faster than that then it may well be that Trident will not be able to hide. And if that’s right, then if we are to bet everything on mutually assured destruction, we have to be assured that it is going to work," she told Today.
"There are forthcoming generations of drones that can work under seas. Now at the moment they have two problems; one is communications and the other is battery life.
"But I was explaining to the PLP that I’d actually met one of the Young Turks at the moment who is developing these drones. And they are very hopeful that in the next 10 years or so that actually the seas will no longer be opaque."
Thornberry said of the row at the meeting of Labour MPs and peers: "Four or five, perhaps possibly six people at the PLP last night kicked off. But I don’t think they necessarily represent the whole of the parliamentary Labour party."
Former Labour minister Lord West was critical of Thonrberry
Lord West was one of several Labour figures who tore into Thornberry during last night's meeting of the PLP.
During the meeting of Labour MPs, Thornberry's critics dismissed her performance as "waffly and incoherent" and "woeful".
One MP, Madeleine Moon, who sits on the NATO parliamentary assembly, tweeted her opinion of Thornberry shortly after leaving the meeting in the Commons.
Asked this morning if, as defence secretary, she would ever use nuclear weapons, Thonrberry said: "If nuclear weapons need to be threatened then they have failed.
"Everybody says that, the whole point is about nuclear weapons is that you don’t use them. In order for them to work at all, you have to be able to say with confidence 'I have a big stick, my stick is larger than your stick', and both sides need to be confident that actually that threat is a real one."
Corbyn triggered an internal-shadow cabinet row over the renewal of Trident in September after he told the BBC he would never authorise the use of Britain's nuclear weapons.
Burnham, who is a supporter of Trident renewal, said the meeting "confirmed something many of us had long suspected: that the debate on Trident in the Labour Party is going to be very difficult".
He told BBC Radio 4's Today: "There are two positions here which are difficult to reconcile - maybe impossible to reconcile - and the party has got to find some way of accommodating those positions and move forward and don't let this issue take over everything."
In an apparent dig at Corbyn's suggestion that a new fleet of nuclear submarines could be deployed without warheads, he said: "There are some hybrid options that have been put forward but I think most people have found that they just don't work.
"So the discussion has been in the party: 'can you realistically try to find a halfway house?' and most people have concluded that you can't.
"Therefore if there are two positions that are deeply held on both sides but can't easily be reconciled, 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."