(Bloomberg) -- Sajid Javid quit as the U.K.’s Chancellor of the Exchequer as Boris Johnson’s first major Cabinet reshuffle went disastrously wrong.

The finance minister resigned after a face-to-face row with Johnson inside 10 Downing Street. The prime minister demanded that Javid fire all five of his most senior aides but the chancellor refused and quit, according to three people familiar with the matter.

Javid had served as Britain’s finance minister since July 2019. His departure throws Britain’s preparations for life outside the European Union into chaos, just four weeks before he was due to deliver a budget on March 11. Johnson’s office named Javid’s deputy Rishi Sunak as the new chancellor.

Javid stood for leadership of the Conservative Party against Johnson last year, coming fourth in the race, before being appointed chancellor.

He has been locked in a power battle with Johnson’s top adviser Dominic Cummings for months. Last year, a furious Javid confronted Johnson and Cummings, over the dismissal of Sonia Khan, his media adviser. Cummings had fired her on Aug. 29 after accusing her of lying about being in contact with former colleagues close to Javid’s predecessor, Philip Hammond, who is committed to preventing a no-deal Brexit.

One of five sons of Pakistani immigrants, Javid worked in business and finance before joining Parliament in 2010, with roles at Chase Manhattan Bank and Deutsche Bank. A major figure in the Tory party, he has held various Cabinet posts, including the culture, business and housing portfolios.

Javid is replaced by Sunak, currently chief secretary to the Treasury. He is seen as a rising star in the Conservative Party, who worked at Goldman Sachs and in hedge funds before his career in politics.

Elected to Parliament in 2015, Sunak backed Brexit and was promoted to his Treasury role by Johnson last year.

Sunak, who studied at Oxford and has an MBA from Stanford, represented the Tories in TV debates during the 2019 general election.

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To contact the reporters on this story: Joe Mayes in London at jmayes9@bloomberg.net;Jessica Shankleman in London at jshankleman@bloomberg.net;Robert Hutton in London at rhutton1@bloomberg.net

To contact the editors responsible for this story: Tim Ross at tross54@bloomberg.net, Flavia Krause-Jackson

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