British MPs on Tuesday agreed to hold an early election on December 12, backing Prime Minister Boris Johnson's call to try to break the crippling political deadlock that has seen Brexit delayed three times.
Hours after the EU formally agreed to postpone Britain's departure again, up to the end of January, parliament voted for the country's third election in four years.
It is a gamble for Johnson, who leads a minority Conservative government, but he had nowhere left to turn after MPs rejected the Brexit terms he struck with Brussels less than two weeks ago.
His Conservatives are currently well ahead of the opposition Labour party in opinion polls, and he hopes to win a majority in the lower House of Commons in order to push through his Brexit plan.
But his failure to keep to his "do or die" pledge to leave the EU on October 31 risks a backlash among eurosceptic voters.
The election outcome could have huge implications for Britain's tortuous Brexit process, which began with the 2016 EU referendum.
Labour is committed to a new "people's vote", while two smaller opposition parties want to reverse Brexit.
Many Labour MPs are wary of an election, fearful of defeat under their leftist leader Jeremy Corbyn, but he swung his support behind the poll.
Ahead of the vote in parliament, European Council President Donald Tusk confirmed the formal adoption of Monday's decision by EU envoys to accept a Brexit delay of up to three months.
"To my British friends, The EU27 has formally adopted the extension. It may be the last one. Please make the best use of this time," he tweeted.
The election bill will now go to the unelected upper House of Lords for debate on Wednesday, but peers are expected to back the plan, paving the way for parliament to be dissolved early next week.
Johnson took office in July promising to end the wrangling over Brexit which has bitterly divided the country, but a rebellion over his hardline strategy left him without a majority in parliament.
Unable to win MPs' support for new divorce terms he struck with Brussels, he was forced by law earlier this month to ask EU leaders for a delay.
After three failed attempts to pass a normal election motion, which requires the support of two-thirds of MPs, Johnson on Tuesday took an alternative path.
He introduced a bill to legislate for an election -- a method which required only a simple majority, and passed by 438 votes to 20.
"We are left with no choice but to go to the country to break free from this impasse," he had told MPs.
A newly elected parliament would have a "new mandate to deliver on the will of people and get Brexit done", he said.
In a move to unite his Conservative party ahead of the poll -- the first in December since 1923 -- Johnson readmitted 10 of the 21 MPs he expelled last month for defying his Brexit plan.
Corbyn had sought to amend the government's bill to hold the election on December 9, but this was defeated by 315 votes to 295.
The veteran socialist had been torn between rival camps within his own party over whether to proceed with the vote.
But the smaller Scottish National Party and the Liberal Democrats wanted a vote, making it hard for Labour to stand in their way.
Corbyn had publicly argued that he would not allow an election until Johnson's threat to leave the EU without a divorce deal was removed.
The EU's decision to delay Brexit meant that "for the next three months, our condition of taking no-deal off the table has now been met", he announced.
"We will now launch the most ambitious and radical campaign for real change our country has ever seen."
'Boris Has To Win'
Experts warn that British politics remains deeply volatile almost three years after the referendum vote, and say the result could be unpredictable.
There was significant voter switching between the 2015 and 2017 elections.
Election specialist John Curtice from the University of Strathclyde in Glasgow said Johnson is in a strong position to get a majority -- but an election remains a gamble.
"Boris has to win. A hung parliament and Boris is out," he said, warning that a Labour-led coalition would likely take over.