LONDON — Prime Minister Theresa May stunned Britain Tuesday (Apri 18) by announcing that she would call an early election on June 8, placing a bet that voters would give her Conservative Party a strong mandate as her government negotiates the country's withdrawal from the European Union (EU).

"The country is coming together, but Westminster is not," Mrs May said in an unscheduled appearance outside 10 Downing Street, referring to divisions in Parliament, adding that she had "only recently and reluctantly come to this conclusion".

The pound strengthened by almost half a cent against the dollar and 10-year British government bond yields rose slightly after the announcement.

Mrs May had repeatedly ruled out a snap election, so her decision Tuesday represents an abrupt reversal.

Her spokesman later said Britain's timetable for leaving the EU will not be affected by Mrs May's decision, adding that work towards a Brexit deal would continue.

"It carries on exactly as it is. Officials carry on working and you continue to have secretaries of state working on this."

European Council president Donald Tusk said Mrs May's decision is a Brexit plot twist worthy of master of suspense Alfred Hitchcock.

"It was Hitchcock, who directed Brexit: First an earthquake and the tension rises," tweeted Mr Tusk, referring to a remark widely attributed to the British-born Hollywood film-maker that a good movie "should start with an earthquake and be followed by rising tension".

In calling an early election, Mrs May is betting that voters will give the Conservative Party, which holds a slim majority - 330 seats in the 650-member House of Commons - a stronger mandate.

She also hopes the election will boost her slim majority in Parliament and give her a new mandate to put her stamp on domestic reforms in education and health and strengthen her hand in talks with the EU, which will start in earnest in June. Opinion polls give her a strong lead and she has faced opposition from her own party for some of her domestic reforms.

The Conservative Party is around 20 points ahead of Labour, a large lead for an incumbent party two years after the last parliamentary election.

The Prime Minister's personal ratings also dwarf those of Labour leader Jeremy Corbyn, with 50 per cent of those asked saying she would make the best Prime Minister. Mr Corbyn wins only 14 per cent, according to pollster YouGo.

Within an hour of Mrs May's comments, Mr Corbyn said that Labour would welcome an early election - even though many of his critics in the party fear that it will lose seats.

Parliament is scheduled to vote Wednesday on the matter. But Mrs May's announcement is also a huge gamble.

A new election will reopen some of the country's gravest divisions. It will give Brexit opponents another chance to soften the terms of the withdrawal from the EU by voting for Liberal Democrat and Labour lawmakers who favour the bloc. It will give the Scottish National Party, which grabbed dozens of seats from Labour in the 2015 national election a new chance to reissue its call for Scottish independence.

If Western democracies have learnt anything over the past year, it is that elections are unpredictable. And if Mrs May wins anything less than a commanding majority on June 8, she will be weakened.

Mrs May took power in July; her predecessor, Mr David Cameron, resigned after voters narrowly approved a referendum supporting departure from the EU, a decision known as Brexit.

Last month, Mrs May formally initiated the two-year divorce process, one of Britain's most consequential decisions since World War II.

She said her decision to call an election was a response to gridlock created by the opposition.

"In recent weeks, Labour have threatened to vote against the final agreement we reach with the European Union," she said. "The Liberal Democrats said they want to grind the business of government to a standstill. The Scottish National Party say they will vote against the legislation that formally repeals Britain's membership of the European Union. And unelected members of the House of Lords have vowed to fight us every step of the way."

She added: "If we do not hold a general election now, their political game-playing will continue."

But her critics were quick to jump on the reversal. "This announcement is one of the most extraordinary U-turns in recent political history, and it shows that Theresa May is once again putting the interests of her party ahead of those of the country," Ms Nicola Sturgeon, the leader of the Scottish National Party, said in a statement. AGENCIES