The cross-party rebels are fighting to prevent a no-deal Brexit because of fears it would gravely damage the economy and plunge Britain into a prolonged recession while also leading to possible medicine and food shortages. The vote came hours after Johnson suffered a key defection from his party, costing him his working majority in Parliament.
Johnson and his backers say these fears are overblown and that voters who backed Brexit are demanding action, not more talk.
On a day of high drama and acerbic debate in the House of Commons, lawmakers returned from their summer recess to confront Johnson over his insistence that the U.K. leave the European Union on Oct. 31, even without a withdrawal agreement to cushion the economic blow. Many shouted, "Resign!"
A new election would take Britain's future directly to the people for a third general election in four years. It is not clear Johnson would immediately get the two-thirds majority in Parliament needed to call a fresh vote because opponents are wary he might postpone the election date until after Brexit has taken place, in effect ramming through a no-deal exit.
"I don't want an election but if MPs vote tomorrow to stop the negotiations and to compel another pointless delay of Brexit, potentially for years, then that will be the only way to resolve this," Johnson said minutes after he lost the vote in Parliament.
Earlier Tuesday, two other prominent Conservatives signaled their decision not to seek re-election rather than follow Johnson's Brexit policy. Former Cabinet minister Justine Greening and former Foreign Office Minister Alistair Burt also signaled their intention to step down.
Jeremy Corbyn, leader of the main opposition Labour Party, said he will not agree to a new election until legislation preventing a "no-deal" exit is in place.
"He isn't winning friends in Europe. He's losing friends at home. His is a government with no mandate, no morals and, as of today, no majority," Corbyn said.
Johnson, who became prime minister in July, has tried to crack down on members of his Conservative Party who oppose his Brexit plans, warning they would be expelled from the party if they supported parliamentary efforts to block or delay the withdrawal.
His stance has infuriated many longtime, prominent party members.
Dominic Grieve, who was attorney general in David Cameron's government, says the expulsion threats demonstrate Johnson's "ruthlessness." Greening said she feared her beloved party was "morphing into Nigel Farage's Brexit Party," in a reference to the U.K.'s foremost euroskeptic and the party he leads. Former Treasury chief Philip Hammond warned of the "fight of a lifetime" if officials tried to prevent him from running in the next election.
Time to block a no-deal departure is running short. Johnson last week maneuvered to give his political opponents even less time to block a chaotic no-deal Brexit, getting Queen Elizabeth II's approval to suspend Parliament. His outraged critics sued, and attorneys arguing the case at a court in Scotland completed submissions Tuesday. The judge could rule as soon as Wednesday. Two other major legal challenges to the suspension are pending.
A no-deal Brexit will sever decades of seamless trade with Europe's single market of 500 million people. Leaked government documents predicted disruptions to the supply of medicine, decreased availability of fresh food and even potential fresh water shortages because of disruption to supplies of water treatment chemicals.
Johnson insists the potential threat of leaving without a deal must remain as a bargaining chip in negotiations with the EU.
Though the EU is Britain's biggest trading partner, a no-deal Brexit would also hurt Europe — a fact not lost on Brussels. Johnson's supporters said lawmakers were weakening the government's negotiating position with the EU.
"The one thing that has helped focus minds in the EU is that we're leaving come what may and we've got a very focused task of what a good deal would look like," Foreign Secretary Dominic Raab told ITV. "But the lingering doubt they've got is: Will the shenanigans in Parliament somehow lead to the cancellation or the delay of Brexit?
"That's encouraging them, and weakening our position to actually get the deal we all want."
The bloc insists it won't renegotiate the agreement struck with former Prime Minister Theresa May, which Johnson considers unacceptable.
Johnson has told French President Emmanuel Macron and German Chancellor Angela Merkel he could come up with a better alternative to the main sticking point in the stalled negotiations — the deadlock over how to ensure there are no customs checks between the U.K.'s Northern Ireland and EU member Ireland after Brexit.
Only 58 days before the scheduled exit, the EU said it had received no proposals from the British government aimed at overcoming the impasse, undercutting Johnson's claim that progress is being made.
European Commission spokeswoman Mina Andreeva said the EU's executive body, which supervises talks on behalf of Britain's 27 European partners, is operating on the "working assumption" that Britain will leave the bloc Oct. 31.
Any British request for an extension would have to be approved by each of the other 27 EU nations before it could be granted.
Associated Press writer Lorne Cook in Brussels contributed.
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