Steve Barclay has been named the new Health Secretary, Whitehall sources told PA, after Boris Johnson was forced to appoint his own Chief of Staff to the top job.
Mr Barclay was already doing two jobs, also serving as a Cabinet Office minister, but he was moved tonight after Sajid Javid and Chancellor Rishi Sunak resigned.
Mr Johnson held crisis talks with aides after the two resignations just nine minutes apart - which sources claimed were not co-ordinated.
But despite mounting a swift Cabinet reshuffle, the Prime Minister was running out of loyalists as he was accused of lying about what he knew about "grope" accused MP Chris Pincher.
There was speculation tonight that Mr Barclay would leave the Chief of Staff job to focus full-time on health.
His promotion came as Mr Javid dramatically quit his post, saying he could "no longer, in good conscience, continue serving in this government".
In a swipe at the PM, he said: "The tone you set as leader, and the values you represent, reflect on your colleagues, your party and ultimately the country."
He said Mr Johnson had lost his confidence after failing to accept that the recent Tory no confidence vote was "a moment for humility, grip and new direction".
In reply, the PM said he had served with "distinction" and he was sorry to see him leave his post.
It is the most senior job so far for Mr Barclay, who has risen steadily through Tory ranks and was seen as a solid operator in a new-look No10 team.
The former Axa insurance lawyer and dad-of-two was born in 1972, the son of a union official and civil servant, and grew up with three brothers who all played rugby.
Mr Barclay went to £12,000-a-year King Edward VII school in Lytham St Annes, Lancashire, and studied history at Cambridge. He spent his gap year in the army - serving with the Royal Regiment of Fusiliers.
He was promoted to a government whip under David Cameron in 2015 before rattling through junior ministerial jobs - first at the Treasury, then at the Department of Health.
He was later named Brexit Secretary under Theresa May and stayed loyal to Boris Johnson, becoming his Chief of Staff and Cabinet Office minister.
