A Whitehall leak inquiry has been launched in an attempt to find out who passed details of Chancellor Rishi Sunak’s wife’s tax status to the media.

Akshata Murty dramatically announced on Friday that she would pay UK taxes on her worldwide income after the disclosure she was “non-domiciled” in the UK for tax purpose sparked a political storm.

Labour accused Mr Sunak of hypocrisy, saying his family had potentially saved tens of millions of pounds as a result of the arrangement while he was putting up taxes for millions of others.

The PA news agency understands that an investigation is now under way to establish how the information was passed to The Independent online newspaper.

Mr Sunak’s team is said to believe that it is a Labour supporting official dubbed “red throat”, according to The Sunday Times.

The paper quoted a senior Government official as saying: “There’s going to be a full Cabinet Office and HM Treasury investigation into who had that information and if anyone has requested that information.

“Divulging the tax status of a private individual is a criminal offence.”

Some experts have estimated that Ms Murty, who remains an Indian citizen, has saved £20 million as a result of not having to pay taxes on her shares in Infosys, an Indian IT company founded by her father.

The disclosure saw Mr Sunak’s approval ratings take another hit after he was criticised for not doing enough to support families struggling with the cost-of-living crisis in last month’s Spring Statement.

A poll by Opinium Research found his approval rating dropped by three points since late March to 28%, while his disapproval rating rose by eight points to 43% giving him a net rating of -15 (minus 15).

It has led to questioning among Tory MPs as to whether the Chancellor – long seen as a potential successor to Boris Johnson – has the political judgment needed for the top job.

Meanwhile sources close to Mr Sunak played down reports that he was moving his wife and two daughters out of Downing Street to escape the glare of the media.

The Sunday Times reported that removal vans arrived in the street on Saturday to take their belongings away.

One source said however they had always intended to spend more time in their west London home as their elder daughter, Krishna, entered her final term of primary school before moving on to secondary school.

Mr Sunak is expected to stay in Downing Street during the week while joining them at weekends.