Ms Murty is the daughter of Narayana Murty, an Indian billionaire in whose IT company Infosys she owns shares.

Last year she was entitled to receive a dividend of £11.6 million, according to company filings. Under her non-dom arrangement, she only paid tax in the UK if any of the money was brought to Britain.

However, in her statement, she said she would pay UK tax on the financial year that has just finished, which ran from April 2021 to this April. It means that, as well as the Indian tax rate of £1.2 million she has already paid, she is reportedly now set to pay £3.4 million in UK tax.

A spokesman for Ms Murty initially argued that she was a non-dom because her Indian citizenship prevented her from having citizenship of another country. However, later it emerged that the tax status had been a choice.

Despite her decision on tax, as an Indian Ms Murty will retain her non-domiciled status indefinitely.

Richard Murphy, a tax expert, said this means she might still be able to avoid UK capital gains tax and inheritance tax, adding: “This is a massive tax advantage: her potential inheritance tax bill is thought to be as much as £280 million on her shares in Infosys, which are estimated to be worth £700 million.”

The statement is one of the first times Ms Murty has talked publicly about her relationship with Mr Sunak and their family life.

She said: “Until now, I have tried to keep my professional life and my husband’s political career entirely separate. Since Rishi entered Parliament, he has not involved himself in my business affairs and I have left politics to him.

“When I met him, we were 24-year-old business school students, living in another country, and had no idea of where life would take us.”