Boris Johnson is set to chair the first meeting of his new-look Cabinet after a dramatic reshuffle which saw Sajid Javid quit as chancellor.
Several senior heads rolled as the Prime Minister recast his top ministerial team on Thursday.
Mr Javid had been ordered to fire his closest aides and replace them with advisers chosen by Number 10.
But the MP chose to quit instead and was replaced by his former deputy at the Treasury, Rishi Sunak, in the biggest shock of Mr Johnson’s shake-up.
Mr Javid accused the PM of setting conditions “any self-respecting minister” would reject – seen as a thinly veiled swipe at his successor.
The bombshell – less than a month before the Budget – follows tensions between the ex-chancellor and the PM’s chief adviser Dominic Cummings.
In August, Mr Cummings fired Mr Javid’s aide Sonia Khan and it appears Number 10 wanted to go further in keeping a closer eye on him.
The move – viewed by critics as a power grab by Mr Cummings – means Britain is on to its third chancellor in a year.
Downing Street refused to guarantee that next month’s Budget would go ahead as scheduled.
A spokesman said only that “extensive preparations have already been carried out for the Budget and they will continue at pace”.
Mr Javid’s departure came after Julian Smith was unceremoniously dumped as Northern Ireland secretary.
He had just weeks ago brokered the deal that restored the power-sharing administration at Stormont.
In other moves, Andrea Leadsom was sacked as business secretary and Theresa Villiers lost her job as environment secretary.
Geoffrey Cox was removed from his post as attorney general and Esther McVey lost her role as housing minister,
The total number of women attending Cabinet fell from eight to seven – while the total number of ministers attending shrank from 32 to 26.
Along with the ministerial exits, the reshuffle included promotions for MPs who are highly rated by Number 10.
Alok Sharma was promoted from international development to become the new Business Secretary.
He will also be minister for the COP26 UN climate summit, which is due to take place in Glasgow in November.
Anne-Marie Trevelyan joined the Cabinet as International Development Secretary, having previously been a defence minister.
Oliver Dowden became a full Cabinet member as Culture Secretary, having previously attended the meetings as paymaster general.
George Eustice was promoted to Environment Secretary from his previous role in the same department.
Brandon Lewis was appointed as Northern Ireland Secretary, and former Brexit minister Suella Braverman returned to the Government as Attorney General.
Former Brexit secretary Stephen Barclay has replaced Mr Sunak as Treasury Chief Secretary.
Amanda Milling was made Conservative Party chairman – a role in which she will attend Cabinet as a minister without portfolio.
Former defence secretary Penny Mordaunt will return to Government as Paymaster General in the Cabinet Office.