Nominations were opening Wednesday to replace British Prime Minister David Cameron as leader of the Conservative Party, with the victor getting the challenge — or the poisoned chalice — of becoming the country’s next leader and negotiating Britain’s exit from the European Union.

Cameron announced his resignation after British voters decided last week, against his advice, that the U.K. should leave the 28-nation bloc.

The first contender to make it official was Work and Pensions Secretary Stephen Crabb, who said he was running because “I don’t see anybody who provides a compelling answer” to the question of how to heal a deeply divided nation.

The 43-year-old Crabb, raised by a single mother in public housing, said he would offer “resilience, optimism, humility, strength.” Although he backed the “remain” side in the referendum, he promised to deliver a “negotiated exit” from the EU.

Crabb is running with Business Secretary Sajid Javid — who would serve as his finance minister — on what has been dubbed a blue-collar ticket. Both men come from working-class backgrounds, in contrast to upper-crust front-runner Boris Johnson, the former mayor of London, and the current prime minister, Cameron.

Johnson, who led the “leave” side in the referendum, has the support of several senior Tory lawmakers. Environment Secretary Liz Truss wrote in the Daily Telegraph that she was backing the 52-year-old Johnson because the new leader must be “someone who believes in, and campaigned for, leaving the EU.”

Home Secretary Theresa May, who backed the “remain” side but is seen as competent and experienced, is also expected to run.

May, 59, could appeal to a large chunk of Conservatives who mistrust the flamboyant, Latin-spouting Johnson, who has been accused of using the referendum as a platform for his leadership ambitions and of failing to draw up plans for a “leave” win.

Tory lawmaker Alan Duncan compared Johnson to the erratic former Italian Prime Minister Silvio Berlusconi, dubbing him “Silvio Borisconi.”

After nominations close at noon Thursday, Conservative lawmakers will vote and whittle the candidates down to two. Those names will be put to a postal vote of all party members with the result expected in early September.

The opposition Labour Party is also in turmoil at the top, with leader Jeremy Corbyn resisting intense pressure to resign.

On Tuesday, Labour members of Parliament passed a no-confidence vote on Corbyn by 172-40. But Corbyn says he has the support of grass-roots party members and will not resign.

Many Labour supporters accuse Corbyn of failing to make a strong case to Britons during the campaign as to why they should stay in the EU.

Former Labour Cabinet minister Tessa Jowell said the party was in “a complete shambles.”

“It is a statement of the obvious that Jeremy has got to stand down and allow a new leader to rebuild the party,” she said.

The imminent departure of Cameron and the rebellion against Corbyn gave a surreal tone Wednesday to the normally raucous Prime Minister’s Questions session in the House of Commons.

Labour Party lawmakers declined to cheer Corbyn and sat in stony silence as he quizzed Cameron on the economic implications of a British exit — or Brexit. Cameron, for his part, made a sharp attack on Corbyn, saying it was not in the national interest for him to keep his job.

“For heaven’s sake man, go!” Cameron urged the Labour leader.

(AP)