Labour leader Sir Keir Starmer has said the Prime Minister must give an assurance that no cabinet minister has ever used “schemes” to lower their tax burden.

Chancellor Rishi Sunak’s political career is at risk of being derailed by the row over his wife’s non-domiciled status and his own former holding of a US green card, along with the announcement on Tuesday that he had been fined by the Met for breaching Covid-19 lockdown rules.

Speaking during a visit to Glasgow on Tuesday, Sir Keir said the Prime Minister should be clear that no cabinet ministers have used such “schemes” in the past or are currently using them.

“What I want from the Prime Minister is an assurance as to whether other members of his Cabinet have been using schemes, either now or in the past, to reduce their own tax burden in this way,” he said.

“Because they’ve all been out telling everybody else they’ve got to pay their taxes, there’s no option but to increase their taxes.

“We’re entitled to know if other members of the Cabinet have been using these schemes.”

Sir Keir said there was no need for a “long investigation, just a simple yes (or) no”.

The Labour leader went on to say that there is “nothing unfair” about questioning the finances of the Chancellor’s wife in this manner.

“There is nothing unfair about criticising a Chancellor who says to millions of people ‘I’ve no option but to put your tax up’ whilst at the same time it appears his own household may have been using schemes to reduce their own tax,” Sir Keir said.

“That’s a very obvious conflict of interest.

“I think that on behalf of everybody that is really struggling with their bills and the cost of living with increased taxes, they’re entitled to know basic answers to basic questions.

“Quite frankly, the sooner the Chancellor gets on and answers those questions the better for everybody.”

It has been estimated that her non-dom status could have saved her £20 million in taxes on dividends from her shares in Infosys, an Indian IT company founded by her father.

Public records show Infosys has received more than £50 million in UK public sector contracts since 2015, with Labour arguing Mr Sunak should have registered an interest in the firm, because of his wife’s involvement.

Mr Sunak has ordered a full-scale investigation by the Cabinet Office and the Treasury into who leaked details of his wife’s tax status to The Independent, which triggered the row.

Speculation at Westminster has suggested a Labour-sympathising civil servant or rivals in No 10 could have been behind the leaking of the confidential information.

Tensions between No 10 and the Chancellor have increased following a spring statement which was criticised for not doing enough to help address the cost-of-living crisis.

Boris Johnson has agreed to a request from Mr Sunak asking for Lord Geidt, the Prime Minister’s independent adviser on ministerial interests, to review all his declarations of interest since he became a minister in 2018 to ensure they had been properly stated.