The Government's ethics watchdog has been asked to launch a probe into Rishi Sunak's decision not to declare parts of his wife's financial affairs in the register of ministerial interests.

Labour MP Tonia Antoniazzi has written to Lord Evans, the chair of the committee on standards in public life, to ask him to examine whether the Chancellor had breached the ministerial code.

Mr Sunak’s wife, Akshata Murty, is richer than the Queen due to a £430million shareholding in Infosys, an IT firm founded by her father, according to The Guardian.

The Chancellor did not mention this in his entry in the official register, nor her shareholdings in at least six UK companies, the paper said.

Rishi Sunak MP and wife Akshata Murthy

Government ministers are required to declare any financial interests that might be relevant to their role, which includes those of their close family members.

In her letter to Lord Evans, Ms Antoniazzi said: "The reports around the chancellor’s financial affairs are extremely concerning, and I am writing to ask you to assess whether this is a direct contravention of the ministerial code of conduct."

Shadow financial secretary to the Treasury, James Murray, said the revelations raised “serious questions” about the Chancellor’s conduct.

Mr Sunak is understood to have met the Government's ethics chief Helen MacNamara in 2019 - before he was appointed Chief Secretary to the Treasury - to discuss his financial interests.

She offered him advice on what he and his wife needed to declare.

Ms MacNamara confirmed at the time and again recently that she was satisfied with his entry in the register.

A Treasury spokesman said: “The Prime Minister’s independent adviser on ministerial interests has confirmed he is completely satisfied with the Chancellor’s propriety of arrangements and that he has followed the ministerial code to the letter in his declaration of interests.”