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Pressure intensified on Labour Party leader Jeremy Corbyn to resign on Wednesday, with Britain’s outgoing prime minister, the country’s last Labour prime minister and Corbyn’s predecessor as Labour leader all urging him to step aside.

The calls came just a day after Corbyn suffered a humiliating defeat at the hands of his fellow Labour members of Parliament, with 172 of them expressing no confidence in his leadership through a secret ballot. Only 40 backed the leftist politician.

The indignity continued Wednesday in the most public way possible: At the weekly political joust known as Prime Minister’s Questions, soon-to-be-departed Prime Minister David Cameron told Corbyn: “For heaven’s sake, man, go!”

Labour Party leader Jeremy Corbyn suffered a humiliating defeat at the hands of his fellow Labour members of Parliament on Tuesday. (Lauren Hurley/AP)

The comment elicited rapturous cheers from Cameron’s Conservative benches and silence from Labour.

Despite his fast-crumbling position, Corbyn continued to cling to what remains of his power. He has steadfastly refused to step aside, even as the Labour Party has veered toward a possible breakup if he won’t go.

The stalemate is part of the continuing fallout from Thursday’s referendum on Britain’s membership in the European Union.

Cameron said hours after the vote that he would step down, having led a failed “remain” campaign.

But Corbyn has refused to accept responsibility for what critics see as his key role in the “remain” campaign’s defeat. Although the north London politician was ostensibly in favor of Britain staying in the E.U., he was an indifferent campaigner. And “leave” won in Labour heartlands that had been seen as critical to any hope of avoiding a British exit from the E.U. — popularly known as Brexit.

Cameron on Wednesday attacked Corbyn directly for a lackluster effort. “I know the honorable gentleman says he put his back into it,” the prime minister said as Corbyn sat frowning on the opposite bench in the House of Commons. “All I’d say, I’d hate to see him when he’s not trying.”

Cameron said that it helped the Tories for Corbyn to hang on but that “it’s not in the national interest.”

Corbyn’s two immediate predecessors as Labour leader, Gordon Brown and Ed Miliband, also urged him to go.

Brown, who resigned as prime minister in 2010, told Sky News that Corbyn had lost the faith of his parliamentary colleagues and predicted he would ultimately step aside.

Miliband, a former Corbyn backer, warned on Facebook that he was creating “a wrecked, divided party.”

With Corbyn refusing to budge, some of Labour’s more moderate members have explored creating a splinter party.

Corbyn’s election to the leadership in September was a lurch to the left for a party that governed from the center-left for 13 years under Brown and Tony Blair.