Boris Johnson has been elected leader of Britain’s ruling Conservative Party after defeating his rival, Foreign Secretary Jeremy Hunt.
The former Mayor of London, famous for his mop of blonde hair and political and linguistic gaffes, promised Tory members he would deliver Brexit before 31 October, despite a seemingly interminable stalemate in Parliament.
Mr Johnson won 92,153 votes, compared to 46,656 for Mr Hunt but the opposition Labour Party said he had been chosen by just 0.3 percent of the electorate and Jeremy Corbyn challenged him to call a general election.
Mr Johnson replaces Theresa May in 10 Downing Street and will set about reshuffling his Cabinet.
In his first speech as leader, Mr Johnson paid tribute to Mrs May and then moved on to describe what the future holds.
He said many people will question the wisdom of him becoming the Tory party leader and prime minister.
Mr Johnson said: "No one party has a monopoly on wisdom but you will see that we Conservatives have had the best insight to human nature...and time again it is to us that the people have turned."
He said: "I say to all the doubters, we are going to get energised and we are going to get Brexit done."
Mr Johnson said: "We are going to unite this incredible country. We are once again going to believe in ourselves, and like some slumbering giant we are going to rise and ping off the guy ropes of self doubt and negativity."
Commenting on Brexit, he said there was a need to reconcile the desire for free trade and the desire for democratic self-government.
But Scotland's First Minister, Nicola Sturgeon, reacted angrily: "Scotland did not vote for Brexit, or for the current Tory government - and certainly not for Boris Johnson as Prime Minister. All of this underlines the need for Scotland to have the right to determine our own future."
The Chancellor of the Exchequer, Philip Hammond, and Justice Secretary, David Gauke, both said they would resign if Mr Johnson won the contest.
Mr Johnson may decide to retain his rival, Jeremy Hunt, in the Foreign Office to maintain consistency and stability at a time when Britain is engaged in a diplomatic crisis with Iran over the British-flagged tanker Stena Impero.
Iran's Foreign Minister, Mohammad Javad Zarif, congratulated Boris Johnson on Tuesday, 23 July, and said Iran was not seeking confrontation in the Gulf.
Mrs May stepped down after repeatedly failing to get Parliament to ratify her Brexit deal.
Mr Johnson has promised to push through a “no deal” Brexit if he cannot renegotiate a new deal with the European Union, despite fears Tory rebels will ally with Labour and the Liberal Democrats to block a no deal Brexit in Parliament.
The EU has repeatedly said it will not revive talks on the withdrawal deal and Mr Johnson will be forced to engage all his legendary charm to get French President Emmanuel Macron, German Chancellor Angela Merkel and other European leaders to budge.
Mr Johnson arrived at the Houses of Parliament on Tuesday afternoon to address a meeting of the 1922 Committee of Conservative MPs.
It has also emerged that Mr Johnson has chosen to promote Mark Spencer, the MP for Sherwood in Nottinghamshire, to Chief Whip, a key role as he tries to cajole Tory MPs, especially on Brexit.
The Tories are only able to govern at the moment because of the backing of 10 Democratic Unionist Party MPs from Northern Ireland and they are urging Mr Johnson to renegotiate the “Irish backstop” part of Mrs May’s deal, which they fear makes Northern Ireland a separate entity from mainland Britain.
If he is unable to get a new Brexit withdrawal deal and cannot push through a no deal Brexit, Mr Johnson will have little choice but to call a General Election, although many Tory MPs fear they would lose their seats to Nigel Farage’s Brexit Party or to the Liberal Democrats, who are now the party of Remainers and have a new leader, Jo Swinson, who was chosen on Monday 22 July.
Mrs May, 62, has said she intends to stay on as Conservative MP for Maidenhead but is likely to go down in history as Britain's worst prime minister in recent memory.
She congratulated Mr Johnson on his victory and said she would give him her "full support from the back benches".
Anna Soubry, a former Conservative MP, leading Remainer and leader of the Independent Group for Change, said Mr Johnson entering Downing Street was "very bad news for our country".
She said: "It's a bleak day for British politics...I do not believe it has the support of the vast majority of the people of this country - but it does show you the shift of the Conservative Party to the right."