Downing Street has been forced to say Rishi Sunak has never paid a tax penalty in the wake of the Nadhim Zahawi affair.
The prime minister’s press secretary initially insisted that Mr Sunak’s taxes were “confidential”, despite his pledge to publish his return shortly.
But Labour added to Mr Sunak’s woes by saying Sir Keir Starmer has never paid a fine to the taxman.
Within hours No 10 had released a statement saying: “The prime minister has never paid a penalty to HMRC.”
Pressure is mounting on Mr Sunak after he kept Mr Zahawi in his cabinet even as he ordered an investigation into his handling of his taxes.
Mr Zahawi settled an estimated £4.8m bill with HMRC while he was chancellor, including a reported around £1m penalty.
Mr Sunak has promised to release his own tax returns in a bid for transparency after The Independent revealed last year that his wife held controversial non-dom status.
At Prime Minister’s Questions, Labour leader Sir Keir Starmer sought to link Mr Sunak’s handling of the current crisis and his billionaire wife Akshata Murty’s non-domiciled status.
The Labour leader said: “We all know why the Prime Minister was reluctant to ask his party chair questions about family finances and tax avoidance.”
Downing Street has said Mr Sunak will publish his own tax return soon.
But his press secretary would not at first say whether or not he had ever paid a penalty to HMRC.
“You wouldn’t expect me to get into the prime minister’s tax affairs, they are confidential,” she said.
“The tax affairs of an individual, irrespective of who they are, are confidential,” she added.
She also would not commit to publishing six years of his tax returns, as David Cameron did while he was prime minister.
Earlier this month growing pressure forced Mr Sunak to admit he had used “independent” healthcare in the past, despite similar arguments that his personal health details were not “in the public interest”.
Labour said Mr Sunak should reveal whether he has ever paid a tax penalty.