Ms Truss finished her first tranche of appointments late on Tuesday, with new Chancellor Mr Kwarteng tweeting that getting the job was "the honour of a lifetime".

He is expected to spend his first day meeting chief executives of various banks to brief them on his outlook.

Mr Kwarteng is also understood to be finalising plans for energy bill support which would see a typical household bill capped at around £2,500 a year.

Defence Secretary Ben Wallace was one of the few senior minister to retain his job, where he has earned plaudits in his response to the conflict in Ukraine.

Nadine Dorries, who backed Ms Truss, said she had been asked by the new PM to stay on as culture secretary but had decided to quit front-line politics.

Jacob Rees-Mogg, an early supporter of Ms Truss, was appointed business, energy and industrial strategy secretary.

Mr Sunak, the former chancellor whose resignation helped trigger the downfall of Boris Johnson, had already made it clear he did not expect to be offered a new job.

But his supporters had urged Ms Truss to appoint an "inclusive" cabinet and not simply surround herself with loyalists.

Ms Truss was appointed the 56th prime minister of the UK by the Queen, in a ceremony at Balmoral on Tuesday.

She returned to a rain-lashed Downing Street, where in a short speech she vowed to grow the economy through tax cuts and reform; take action to deal with energy bills and put the health service on "a firm footing".

BBC