Downing Street said Queen Elizabeth II had approved the appointment of Zahawi, who came to Britain as a child with his Kurdish family not speaking any English, before forging a lucrative business career.
The 55-year-old co-founded the prominent polling company YouGov and was active in local Conservative politics in London, before becoming an MP in 2010.
He won widespread praise for overseeing Britain’s pandemic vaccines rollout.
But like Sunak, his private wealth has drawn adverse attention, including when he claimed parliamentary expenses for heating his horse stables in 2013.
Zahawi refused to comment to reporters as he left a meeting in 10 Downing Street, including on whether he will uphold Sunak’s pleas for fiscal discipline against Johnson’s free-spending instincts.
The prime minister named another loyalist, Michelle Donelan, to take Zahawi’s place at the education ministry.
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