The Foreign Secretary said he would not run for leadership while negotiations were ongoing, telling Channel 4 News "we have to get on and deliver on the priorities of the people".
Britain will leave the European Union in March 2019 which means that any leadership campaign will take place that summer.
The news clears the way for an interim leader such as David Davis to become the next leader if Theresa May quits, allowing Mr Johnson to take the party into the 2022 election
Tory MPs are openly speculating that there will be a new Conservative leader by Christmas after Mrs May failed to win a majority in the election.
One MP told The Telegraph that he knew of 10 letters of 'no confidence' that have been submitted to Graham Brady, the chairman of the 1922 committee of backbench MPs.
If 48 Tory MPs - 15 per cent of the parliamentary party - submit similar letters, it will automatically trigger a Conservative leadership election.
Earlier this week one ally of Mr Johnson said Mr Davis would be a “serious contender” for the leadership if it was vacated and the “perfect tonic” against a resurgent Jeremy Corbyn after his unexpectedly strong performance in the general election.
Mr Johnson was also forced to deny he had started to plan his leadership bid after photographs surfaced of him and Sir Michael Fallon, the defence secretary and a key ally of Mrs May, sharing a drink in a pub in Kent on Saturday evening.
Last weekend Philip Hammond and Andrea Leadsom, two Cabinet ministers who could also challenge for the leadership, failed to say that Mrs May will still be leader when the next general election is expected to be held in five years’ time.
Mrs May’s stock is at its lowest ebb since she became Prime Minister last year after her gamble to call a general election backfired and she failed to win a majority in the House of Commons.
The Prime Minister was widely criticised for failing to visit the victims of the Grenfell Tower fire tragedy until after the Queen and Labour leader Jeremy Corbyn.
She has still to win the agreement of the Democratic Unionist Party’s 10 MPs to support her policies in the House of Commons and prop up her minority administration.
Talks about a Confidence and Supply deal with the DUP have been continuing for nine days.
http://www.telegraph.co.uk/news/2017/06/21/boris-johnson-will-not-run-leader-march-2019/
