Updated at 7:40 a.m. ET

Britain's Conservative Party has chosen Boris Johnson to become the country's next prime minister, replacing the pragmatic and sometimes colorless Theresa May with a bombastic populist who favors a no-deal Brexit.

Johnson walked to the podium inside London's Queen Elizabeth II Centre, thanking his opponent, Foreign Secretary Jeremy Hunt, and May.

"Today at this pivotal moment in our history," Johnson said, "we again have to reconcile two sets of instincts, two noble sets of instincts, between the deep desire for friendship and free trade and mutual support and security and defense between Britain and our European partners, and the simultaneous desire, equally deep and heartfelt, for democratic self-government in this country."

British Conservative Party politician Cheryl Gillan announced the result, after the Tories' chairman, Brandon Lewis, urged unity.

Members of the party overwhelmingly chose Johnson — a former journalist, foreign secretary and mayor of London who also served in May's Cabinet before quitting last year over the Brexit impasse — over Hunt to become the new head of the party.

The leadership election was triggered by May's resignation two months ago. It came after her government's repeated failure to forge a Brexit compromise with the 28-nation European Union that could also withstand withering opposition in Parliament. May will deliver her final remarks and officially submit her resignation to Queen Elizabeth II on Wednesday.

Johnson, 55, will officially become prime minister and he will have only a few months to devise an exit plan from the EU that is agreeable to both the British Parliament and the bloc's leadership. His transition to No. 10 Downing Street is unlikely to be a smooth one. Many lawmakers oppose a no-deal Brexit and several members of May's ministers have threatened to quit the government altogether rather than serve under Johnson.

Foreign Office Minister Alan Duncan didn't even wait for the results of the poll, choosing instead to resign on Monday, citing "very grave concerns" that Johnson "flies by the seat of his pants."

"[It's] all a bit haphazard and ramshackle," he wrote in his letter of resignation.

Education Minister Anne Milton also tweeted her resignation minutes before the result was announced, saying Britain "must leave the EU in a responsible manner."

Johnson has vowed to leave the EU by an Oct. 31 deadline whether or not a deal is reached. Most economists say such a move could be economically disastrous for Britain and even before his election was made official, the U.K.'s Office of Budget Responsibility warned that a no-deal Brexit could trigger an economic recession.

"We are getting ready to come out on 31 October. Come what may," Johnson told reporters last month.

"Do or die. Come what may," he added.

Former Labour Party Prime Minister Gordon Brown called such a move "an act of economic self-harm."

Others, including Chancellor of the Exchequer Philip Hammond, plan to resign on Wednesday.

The EU has refused to reopen talks on Britain's withdrawal which were painstakingly hammered out over months of negotiations with May's government, but then repeatedly rejected by Parliament.

Minutes after the announcement that Johnson won the race, opposition leader Jeremy Corbyn took to Twitter to say that Johnson won the support of fewer than 100,000 "unrepresentative Conservative Party members" but not the support of the country. "The people of our country should decide who becomes the Prime Minister in a General Election," Corbyn added.

May congratulated Johnson, saying he had her full support "from the back benches."

Nigel Farage, a leader in the charge to leave the EU, wished him well. "Does he have the courage to deliver?" he asked.

Although Johnson remained the clear favorite up to the moment of voting, an incident occurred last month that left some in doubt about the politician. Police were called to the home of Johnson and his partner, Carrie Symonds, following reports of screaming amid an apparent domestic dispute.

Days later, a photo emerged of the couple in a garden, holding hands and smiling in what critics said was a hamfisted effort by the campaign to tamp down the incident. Some on social media also pointed out that the photo appeared to be old, as the length and color of Johnson's famously tousled hair did not match his current style.

In the weeks since, Johnson has dodged questions about the photo's authenticity. His girlfriend is a former a former Conservative Party communications director.

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