Civil war has broken out with the Labour Party as one shadow cabinet minister quit and another was sacked over concerns that Jeremy Corbyn was leading the party to electoral disaster.
Former shadow foreign secretary Hilary Benn was summarily dismissed after telling Mr Corbyn he no longer had confidence in him while Heidi Alexander quit as shadow health secretary after saying a "change of leadership is essential".
Mr Benn said he was "not going to be a candidate for leader of the Labour Party" but insisted that change was needed at the top of the party.
On BBC One's Andrew Marr Show, he said Mr Corbyn "is a good and decent man but he is not a leader".
Amid speculation that a full-blown coup against Mr Corbyn was being launched by shadow cabinet ministers, Mr Benn said it was "increasingly clear" there was concern about his leadership within senior ranks of the party.
Mr Benn said: "At this absolutely critical time for our country, following the EU referendum result, the Labour Party needs strong and effective leadership as we take decisions of huge importance for the future of our country.
"We don't currently have that and there is also no confidence that we will be able to win a general election as long as Jeremy remains leader."
Asked if there would be further resignations, Mr Benn said: "Of course members of the shadow cabinet, as you would expect - certainly in the wake of the referendum result - have been talking to each other.
"It is for each individual to make their own decision, I have made mine and I made my views clear to Jeremy.
"He is a good and decent man but he is not a leader and that is the problem."