British Prime Minister Boris Johnson did personally pay for the refurbishment of his Downing Street flat, a senior minister said on Sunday.

"What I know is the prime minister has personally met the costs of the flat refurbishment and that is what people in Britain want to know," UK Trade Minister Liz Truss told the BBC.

The announcement comes amid growing calls for Johnson to explain how his lavish renovation was paid for, following allegations from ex-chief adviser Dominic Cummings.

Cummings, who was Johnson's strategist on the Brexit referendum campaign, said on Friday that his former boss had once had "unethical, foolish, possibly illegal" plans to get Conservative Party donors to fund a refurbishment of the apartment, which he lives in with his partner, Carrie Symonds, and their son.

Opposition party calls for investigation

Truss could not confirm where the prime minister obtained the money. She declined to comment when asked whether a donor initially paid for the renovation and Johnson then repaid the donor.

"What I agree with is that the prime minister has met the costs, that everything will be declared in line (with the rules) including for tax purposes," she said.

On Friday, Johnson's office said the government had followed the rules over the apartment renovation and that the prime minister had not interfered in a government leak inquiry.

The opposition Labour Party has called for a probe into the refurbishment funding and whether it was a loan.

Labour leader Keir Starmer said the matter was about "integrity" and "taxpayers' money."

"Every day there is more evidence of this sleaze. Frankly, it stinks," he told BBC news.  

Earlier this week, Labour also called for an independent commission on ethics and standards in government to be set up.

The decision followed a scandal involving former Prime Minister David Cameron, who has been criticized for lobbying ministers on behalf of the failed finance company Greensill Capital, in which he held a commercial interest.  

mvb/mm (Reuters, AFP, AP)