A Jeremy Corbyn-led government would make collective decisions about when to use nuclear weapons, Emily Thornberry has said.
The shadow foreign secretary said Labour would be deliberately “ambiguous” about the circumstances in which it would ever deploy the UK’s Trident weapons system in response to threats from other states.
In what appeared to be a major shift in the party’s stance on the issue, she suggested that Corbyn - who has vowed not to use nuclear weapons - would share the decision with senior cabinet colleagues in the event of an imminent threat.
“I don’t necessarily believe that will be a decision made by one individual, I suspect that the way that Jeremy makes decisions is that he takes advice and we work collectively,” she told ITV’s Good Morning Britain programme.
“We will do everything we can in order to protect our country if it becomes necessary. We will make those decisions together and Jeremy listens to his colleagues, particularly those who he knows and respects,” she also told BBC Radio 4’s Today programme.
However, HuffPost UK understands that Corbyn’s stance is that, while he will listen to advice, he will take the final decisions as Labour leader and PM.
One of the first duties of any incoming prime minister is to write a letter of instruction to military chiefs about how to react to a direct nuclear attack.
Within days of becoming Labour leader in 2015, Corbyn made clear he would not personally authorise the use of Trident. Asked if he would use nuclear weapons, he replied: “No.”
And during the 2017 general election, he underlined his stance. Asked how he would react if Britain were under imminent threat from nuclear weapons, he replied:”I would do everything I can to ensure that any threat is dealt with earlier on by negotiations and by talks.
“The idea of anyone ever using a nuclear weapon anywhere in the world is utterly appalling and terrible. It would result in the destruction of the lives and communities and environment for millions of people.”
But Thornberry said that the principle of deterrence relied on enemies not being sure whether a country would use its nuclear weapons.
“The whole idea of a deterrent is that it is ambiguous and who knows when we would use it... if you’re going to have nuclear weapons, there needs to be an ambiguity about whether you would need them or not.”
Asked by ITV’s Piers Morgan how Jeremy Corbyn would react if there were a nuclear attack on the north of England and London, she replied: “Who knows?”
She said there was “a lot of nonsense” talked about the issue of prime ministerial instructions on Trident, pointing out that Margaret Thatcher never discussed the issue.
It was only Theresa May and David Cameron who had broken the convention to say they would press the nuclear button, Thornberry added.
The shadow foreign secretary suggested that close allies of Corbyn, like herself and shadow chancellor John McDonnell, would make a joint decision. In theory such an arrangement could be written into any letter to defence chiefs, but it is unclear how it would work.
“It’s very difficult to imagine how the dynamics would work before a decision was made one way or the other. Whether it would be one person’s decision, whether it would be a group of people’s decision,” she told ITV.
“This is not helpful in terms of being able to paint real pictures of what may happen in reality. Because no one knows in what circumstances in which people might even say to you ‘use your nuclear deterrent now’.
“I am not prepared to go into whether we would use nuclear weapons or not, whether we would make a decision collectively or not, in what circumstances.”
She added: “In principle, Jeremy is not a pacifist. We are not pacifists. There will be times when we need to use military force but when we use it we need to ensure that the use of the military force actually makes the situation better in the long term.”
Defence minister Johnny Mercer said: “The fact that the Shadow Foreign Secretary is openly speculating that her leader could be overruled by a committee on a matter as fundamental as using our nuclear deterrent shows just how weak Jeremy Corbyn really is. Even his closest colleagues don’t trust him.
“If Jeremy Corbyn is unable to make crucial decisions to keep our country safe, he is not fit to be Prime Minister.”
Tory sources added that prime ministers had personal responsibility to give real time orders on use of drone strikes, shoot-to-kill incidents and other emergency situations.
Corbyn has said that Nato is a ‘danger’ to world peace and that it was founded to ‘promote’ the Cold War.
But Thornberry said that the Labour leader now “agrees and accepts our responsibilties” as a member of the transatlantic military alliance.
The Islington South MP, who was herself opposed to Trident renewal but had to accept a Labour party conference decision to approve it, earlier told ITV that the issue was academic because the Tory government had already gone ahead with a multi-billion pound upgrade.
“The decision has been made by this current government. They have decided to renew. We are not committed to renewing it, we are accepting the fact that the government has already committed us to spending this money,” she told ITV.
“Many of us felt there were better uses of that money but that decision has now been made.”