Senior members of the UK government have expressed concern that the row over Chancellor of the Exchequer Rishi Sunak's personal wealth will damage the Conservative Party's chances in local elections next month.

The finance minister has referred himself to the government ethics watchdog following criticism of his wife's tax status and his possession of a United States residency green card, even after he was appointed chancellor.

The chancellor's wife, Akshata Murty, was last week revealed to be registered non-domicile in the United Kingdom, which allowed her to avoid paying huge sums in taxes.

Soon after the disclosure, Murty, who has Indian citizenship, announced that she would pay British taxes on her worldwide income.

Sunak has said he was confident a review by the independent adviser on ministers' interests would find "all relevant information was appropriately declared".

But some Conservative members of Parliament are critical of the way Sunak has handled the row ahead of the May 5 elections.

The Financial Times reported that the party was already braced to lose seats in Parliament following the damage caused by the cost of living crisis and the "Partygate "scandal that involved illegal social gatherings by government staff during the pandemic lockdowns.

The FT quoted one member of the government as saying May 5 was "already going to be bad, but there's no doubt having a chancellor that looks like he's dodging tax in his own household makes it worse".

A separate government source told the paper "everyone is primarily concerned about the local elections and the Rishi stuff is making our situation worse. People are already concerned about the cost of living and partygate, but this has handed Labour another way to kick us".

Another Conservative MP said: "The local elections will be awful, but at least this way they have someone to blame. Time will tell whether (Sunak) can actually survive all of this."

The opposition Labour Party leader Keir Starmer has accused Sunak of "rank hypocrisy" and said that having a spouse who was a nondomicile for tax purposes would create a "very obvious conflict of interest" for any Cabinet minister.

Speaking to The Guardian, Starmer said there was a "broader issue" with politician's "disconnection from people's lives" and doubted the ability of super-rich MPs to relate to the public amid the cost of living crisis.

Starmer called on Prime Minister Boris Johnson to clarify that no other Cabinet ministers were benefiting from non-dom status, or used tax havens.

Under British law, MPs are not allowed to be non-doms under British law. On Sunday, Sajid Javid, the health secretary, admitted to having been a non-dom for six years, but it was before he became an MP.

When asked on Monday, Downing Street did not confirm whether any other ministers had non-dom spouses. A statement from Number 10 said the prime minister still had full confidence in Sunak.