Labour MPs are being "pushed to the brink" by the leadership's refusal to throw the party's weight behind a second referendum, one pro-Remain backbencher has warned.

Ian Murray was speaking amid growing speculation that Labour MPs may quit the party out of frustration with leader Jeremy Corbyn's stance on EU withdrawal.

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Former frontbencher Chuka Umunna said on Thursday he did not "give a damn... about keeping any party together" when compared to the overriding priority of the national interest in avoiding a no-deal Brexit.

And ex-shadow chancellor Chris Leslie told the House of Commons Labour supporters are being "played for fools" by a leadership which would not put into effect a motion passed unanimously at annual conference to keep the option of a second referendum on the table.

Labour says the option of a referendum does remain on the table, but Mr Corbyn's focus in recent weeks has been on his five demands for a Brexit involving a customs union with the EU, close alignment with the single market and matching workplace and environmental protections.

Mr Murray said the party had gone through all of the stages set out in the motion - including seeking an early election - and should now formally move to backing a so-called People's Vote.

"The leadership are doing everything they possibly can to stop that from happening," he told BBC2's Politics Live. "That's why people are increasingly fed up."

READ MORE: Ian Murray: Tories as big a threat to the union as SNP 

He said "a lot" of Labour MPs are "fed up" with the leadership position on Brexit and on anti-Semitism.

He added: "It's not just Labour MPs who are being played for fools, it's the country and Labour Party members and supporters.

"There is a very solid party policy on the table at the moment that was agreed at party conference - and shadow Brexit secretary Keir Starmer took a standing ovation when he mentioned a People's Vote with an option to Remain.

"It's what Labour voters, Labour supporters, Labour members want, it's what the country is increasingly looking at to try to break the impasse in Parliament.

"We have to move as quickly as possible, with 42 days left, to the position of a People's Vote with the option to Remain, because we believe if the leader of the opposition backs it and whips it, we can win it and then we can try to get out of this Brexit mess."

Mr Murray said both Mr Corbyn and Prime Minister Theresa May are "pandering to the extreme wings of their own parties".

He added: "At some point someone is going to have to stand up and do what is in the national interest, and neither leader of any party at the moment is doing that.

"If our leaders can't stand up for our national interest, then they can't have our support."

The Edinburgh South MP said: "If my constituents start losing their jobs on the basis that the Labour Party has facilitated a hard Conservative Brexit, on the basis that they have refused to implement a democratically put-forward motion of Labour Party conference, then we will all have to make our own decisions about whether or not that is in the best interests of the party or the country."

Asked if he could quit Labour, he replied: "I've never considered that, but we are all being pushed to the brink with the issues around Brexit and the issues around anti-Semitism."

He rejected suggestions he is being disloyal to Mr Corbyn.

"My loyalty is to my constituents and to the Labour Party, who want us to move to this position that they democratically agreed," said Mr Murray. "I don't believe in blind loyalty."

Mr Umunna was asked on Thursday whether he would quit Labour if Mr Corbyn refuses to back a second referendum.

The Streatham MP replied: "The job of leaders is to keep the party together. It's not my job, it's the leadership's job.

"When I joined the Labour Party, I intended to be a member on my death-bed. Ultimately whether we keep the party together is a matter for the leadership.
"If the leadership of either party reverts to making party political decisions instead of pursuing the national interest, then they will never, ever be forgiven."