LONDON — British Prime Minister Boris Johnson has abandoned his promise of an October Brexit and pinned his hopes on a December election.

Two days after lawmakers stymied Johnson’s latest attempt to pass his European Union divorce deal, he said Thursday that the only way to break Britain’s Brexit impasse was a general election. Johnson said he would ask lawmakers to vote Monday on a motion calling a national poll for Dec. 12.

To hold an election Johnson must win a vote — by a two-thirds majority — among lawmakers. That looked like a tough task. Parliament has already dealt Johnson a series of setbacks and derailed his promise to take Britain out of the EU on the scheduled date of Oct. 31 “come what may.”

The most recent blow came Tuesday, when lawmakers blocked Johnson’s attempt to fast-track an EU divorce bill through Parliament in a matter of days, saying they needed more time to scrutinize the legislation.

Britain’s next scheduled election is in 2022. To secure an early election, Johnson needs either to win Monday’s vote in Parliament, or lose a no-confidence vote, which opposition parties have refused to call.

The main opposition Labour Party said Wednesday that it would “support a general election when the threat of a no-deal crash-out is off the table.” It had no immediate response to Johnson’s statement Thursday.

Smaller opposition parties said they wanted an election but were wary of doing it on Johnson’s terms.

“The U.K. government has no coherent plan to end the Brexit chaos and a general election will not solve the crisis,” said Adam Price, leader of the Welsh party Plaid Cymru.

Johnson said “it is time, frankly, for this Parliament to make way for a new, fresh Parliament that can deliver on the priorities of the British people.”

An election can only be held if the EU agrees to postpone the U.K.’s departure to prevent a chaotic no-deal exit. Johnson grudgingly asked for a delay until Jan. 31 on the orders of Britain’s Parliament, which wants to avert the economic damage that could come from a no-deal exit.

Though the bloc has not yet given its answer, Johnson said it looked like the EU would grant the delay.

European Council President Donald Tusk has recommended that the other 27 EU nations grant Britain a delay, yet many of the bloc’s members are frustrated at Britain’s interminable Brexit melodrama. But they also want to avoid the economic pain that would come to both sides from a disruptive British exit.

So they are likely to agree, although politicians in France say President Emmanuel Macron is pushing for a shorter extension than the three months that Britain has asked for.

Johnson has vowed that, sooner or later, the U.K. will leave the EU on the terms of the deal he negotiated with the bloc.

He said the Dec. 12 election date would give lawmakers more time to scrutinize his bill, because Parliament would be in session until the formal campaign started Nov. 6.

If lawmakers refuse to approve his deal, Johnson hopes an election will deliver a majority for his Conservative Party, enabling him more easily to deliver on his plans.

Meanwhile, U.K. police and politicians have sounded alarms about what could happen in Northern Ireland under Johnson’s proposed Brexit deal, with the region’s police chief warning that a badly handled divorce from the EU could bring violence back onto the streets.

Police have long warned that if Britain’s departure from the EU imposes a hard border between the U.K.’s Northern Ireland and EU member Ireland, that could embolden Irish Republican Army splinter groups who are opposed to Northern Ireland’s peace process and power-sharing government.