The UK Labour Party has been plunged into chaos as members of the Shadow Cabinet resigned on Sunday morning in protest at Jeremy Corbyn's leadership.

Ian Murray told the BBC just after his resignation as Schdow Scottish Secretary Corbyn is a "decent human being" and principled but: "He can't lead the Labour Party into a general election because he's not likely to win."

Just prior to this, the MP for Ashfield Gloria de Piero stepped down from her role as shadow minister for young people. In a resignation letter seen by the Guardian, she reportedly wrote:

"I have always enjoyed a warm personal relationship with you and I want to thank you for the opportunity to serve in your shadow cabinet. I accepted that invitation because I thought it was right to support you in your attempt to achieve the Labour victory the country so badly needs.

"I do not believe you can deliver that victory at a general election, which may take place in a matter of months. I have been contacted by many of my members this weekend and It is clear that a good number of them share that view and have lost faith in your leadership."

The Shadow Health Secretary Heidi Alexander also resigned this morning, saying the country needed a credible opposition after voting to leave the European Union and that she did not believe Corbyn could provide it.

"As much as I respect you as a man of principle, I do not believe you have the capacity to shape the answers our country is demanding and I believe that if we are to form the next Government, a change of leadership is essential," Alexander wrote to Corbyn in a letter she posted on Twitter.

Shadow Foreign Secretary Hilary Benn also told Corbyn he had lost confidence in his leadership, prompting Corbyn to sack Benn. The EU referendum, which saw 52 per cent of Britons voting to leave the EU, has begun to transform Britain's political landscape, triggering leadership battles in the Conservative Party as well as Labour.

A growing number of Labour MPs have called on Corbyn to resign. Some party members say he failed to assuage concern among the party's traditional supporters over the EU; others that he should have campaigned more in favour of EU membership. Two Labour politicians have submitted a motion of no confidence in Corbyn, which will be debated later this week. Corbyn's spokesman gave no details on Benn's dismissal, but Benn said he had told Corbyn there was widespread concern in the Labour Party about his leadership, after which Corbyn had dismissed him. The Observer newspaper had reported that Benn, who publicly disagreed with Corbyn in September over air strikes on Syria, was gauging support for a move to oust Corbyn. "In particular, there is no confidence in our ability to win the next election, which may come much sooner than expected if Jeremy continues as leader," Benn said in a statement. As things stand, Britain is due to elect a new parliament in 2020. A new Conservative leader will automatically become Britain's new prime minister, but may seek to call an early election to obtain a personal mandate to govern. Some Labour MPs called on the other members of the shadow cabinet - top policy chiefs who hold portfolios mirroring those of the government - to resign from their positions.

"Lots of good people chose to serve in Shadow Cabinet to keep the show on the road. There are no longer good reasons for good people to stay," Wes Streeting said on Twitter.

Colleague Ben Bradshaw called on the shadow cabinet to "act to save the party and for the sake of the country".

On Saturday, Corbyn rejected the calls for him to resign.

Asked whether he would stand for re-election in any leadership contest, he said: "Yes, I'm here."

Additional reporting by Reuters