Theresa May has called a snap general election on June 8, claiming that divisions at Westminster risked hampering the Brexit negotiations.
The Prime Minister will require the support of two-thirds of MPs to go to the country, with a vote scheduled in the Commons on Wednesday.
The move stunned Westminster, as Mrs May and Number 10 have repeatedly insisted she would not seek a general election before the scheduled 2020 poll.
But Mrs May, who has a fragile working majority of just 17 in the Commons, said she wanted ‘unity’ at Westminster as talks on Brexit begin in earnest with the European Union.
She said: ‘We want a deep and special partnership between a strong and successful European Union and a United Kingdom that is free to chart its own way in the world.
‘That means we will regain control of our own money, our own laws and our own borders and we will be free to strike trade deals with old friends and new partners all around the world.
‘This is the right approach, and it is in the national interest. But the other political parties oppose it.
‘At this moment of enormous national significance there should be unity here in Westminster, but instead there is division. The country is coming together, but Westminster is not.’
She acknowledged that she needed a stronger position in the Commons to secure her plans for the UK’s future outside the EU.