The Prime Minister has called a snap general election to be held on June 8.

Theresa May made the announcement in a hastily arranged statement on the steps of Downing Street.

The Conservative leader had repeatedly said no election would be held until May 2020.

On Wednesday, May will table a motion before the House of Commons for the election.

The 2011 Fixed Term Parliament Act means a two-thirds majority of MPs must vote for the motion.

May said: "Division in Westminster will risk our ability to make a success of Brexit and it will cause damaging uncertainty and instability to the country.

"So we need a general election and we need one now because we have at this moment a one-off chance to get this done while the European Union agrees its negotiating position and before the detailed talks begin.

"I have only recently and reluctantly come to this conclusion.

"Since I became Prime Minister I have said that there should be no election until 2020 but now I have concluded that the only way to guarantee certainty and stability for the years ahead is to hold this election and seek your support for the decisions I must take.

"And so tomorrow I will move a motion in the House of Commons calling for a general election to be held on June 8."

Nicola Sturgeon urged voters to "stand up for Scotland" as the country heads for the election.

In a statement released after the announcement, the First Minister said: "She is clearly betting that the Tories can win a bigger majority in England given the utter disarray in the Labour Party.

"That makes it all the more important that Scotland is protected from a Tory Party which now sees the chance of grabbing control of government for many years to come and moving the UK further to the right - forcing through a hard Brexit and imposing deeper cuts in the process.

"That means that this will be - more than ever before - an election about standing up for Scotland, in the face of a right-wing, austerity-obsessed Tory government with no mandate in Scotland but which now thinks it can do whatever it wants and get away with it."

Sturgeon said it was "a huge political miscalculation" by the Prime Minister.

She added: "It will once again give people the opportunity to reject the Tories' narrow, divisive agenda, as well as reinforcing the democratic mandate which already exists for giving the people of Scotland a choice on their future.

Labour is set to back her plans, giving the green light to the general election.

UK Labour leader Jeremy Corbyn said: "I welcome the Prime Minister's decision to give the British people the chance to vote for a government that will put the interests of the majority first.

"Labour will be offering the country an effective alternative to a government that has failed to rebuild the economy, delivered falling living standards and damaging cuts to our schools and NHS.

"In the last couple of weeks, Labour has set out policies that offer a clear and credible choice for the country. We look forward to showing how Labour will stand up for the people of Britain."

Formal negotiations on the country's exit from the European Union are not scheduled to take place until June after the French presidential election.

The last general election was held in 2015.

At the poll the SNP won 56 MPs with the Conservatives, Labour and the Liberal Democrats each picking up one seat.