UK Prime Minister Keir Starmer overhauled his ministerial team Friday in a bid to reset his embattled government after deputy premier Angela Rayner resigned for underpaying a property tax.

Rayner, a figurehead among Labour's left-wing base, quit after an investigation found she had breached the ministerial code over the purchase of a flat in southern England.

Her departure prompted Starmer to carry out the first major cabinet reshuffle of his stuttering 14-month-old premiership.

Starmer replaced Rayner as deputy with foreign minister David Lammy, whose post as Britain's top diplomat will now be taken by interior minister Yvette Cooper, Downing Street announced.

Justice Secretary Shabana Mahmood from Labour's right wing will succeed Cooper at the Home Office, while Lammy will also take on the justice brief, Number 10 added.

'Deeply regret'

Rayner disclosed on Wednesday that she had underpaid stamp duty on an £800,000 seaside apartment in Hove, near Brighton, and had referred herself to the government's independent ethics adviser.

The admission followed days of reports suggesting that she had saved £40,000 ($53,000) by removing her name from the deeds of another property.

Ethics chief Laurie Magnus concluded that Rayner had failed to "heed the caution" of legal advice that said she was liable for a lower surcharge but qualified that this was not expert tax advice.

"I accept that I did not meet the highest standards," Rayner told Starmer in her resignation letter, adding she would also be stepping down as housing minister and deputy leader of the Labour Party.

"I deeply regret my decision to not seek additional specialist tax advice," she added.

Starmer told her he was "very sad" to lose her from government, but added: "You will remain a major figure in our party".

Starmer also changed the environment, business, and science and technology briefs among others, and sacked two ministers from his cabinet.