"Now, more than ever, Britain needs a leader with a proven track record of delivery and economic expertise," tweeted Merriman on Monday (18 July). "Rishi has supported workers, families and the nation through the toughest of times. He’s the hard-working leader we need to restore public trust and transform the nation’s public services and infrastructure."

Five candidates are still in the race to become the next Tory leader, and by extension, the next prime minister following Boris Johnson’s resignation earlier this month.

Former chancellor Sunak, whose resignation along with that of health secretary Sajid Javid triggered more than 50 others, squares off against trade minister Penny Mordaunt, foreign secretary Liz Truss, former equalities minister Kemi Badenoch and chair of parliament’s foreign affairs committee Tom Tugendhat.

Shapps ran, briefly, only to withdraw his candidacy after 48 hours. He is also now backing Sunak. "When I look round the field of candidates, we’ve got many really talented people standing to be the leader of the Conservative Party," said Shapps.

"But the thing that really concerns me is somebody able to step in on day one and lead this country. And that is what Rishi will be able to do. He has proven throughout the coronavirus and many other battles which have come his way that he could lead Britain and be a fantastic prime minister. That is why I’m supporting Rishi for leader."

Transport minister Robert Courts is backing Badenoch, tweeting: "In our new leader, we need not just change but clear principle. A leader with conviction and vision. There’s no doubt Kemi Badenoch has these qualities."

Courts previously backed Shapps for leader.