British Prime Minister Rishi Sunak was chided by Parliament’s standards guardian on Thursday for failing to declare his wife’s financial interest in a childcare firm that stood to benefit from government policy.

Standards Commissioner Daniel Greenberg said Sunak broke the code of conduct for government ministers, but said the mistake was “inadvertent” and that the prime minister should not be sanctioned for the error.

Read: Nearly 2,000 unaccompanied immigrant minors landed in Rome over the weekend

Greenberg opened an investigation in April over Sunak’s failure to declare when questioned by a committee of lawmakers that his wife. Akshata Murthy, held shares in the company Koru Kids, which had been selected to receive government support for childcare firms.

Greenberg said Murthy’s shareholding “was a relevant interest that should have been declared.” But he said the failure stemmed from confusion about the rules rather than an intent to deceive.

“I confirm that the matter is now closed,” he said.

Sunak apologized for the mistake.

Read: Europe gripped by extreme weather as 'era of global boiling' arrives 

The finding follows a string of ethics breaches by members of Britain’s Conservative government.

Former Prime Minister Boris Johnson was driven from office in mid-2022 when his own Cabinet turned on him after a string of scandals over his judgment and finances.

Read: Putin profits off US and European reliance on Russian nuclear fuel

Sunak vowed to restore order and integrity to government after three years of turmoil under Johnson and briefly serving successor Liz Truss, who quit within weeks after her policies rocked the U.K. economy. But Sunak, a former investment banker, has faced questions about his wealth and the financial arrangements of his wife, the daughter of an Indian billionaire.

Last year, it was revealed that Murthy didn’t pay U.K. tax on her overseas income, including 11.5 million pounds ($15 million) a year in dividends from Infosys, the Indian IT company founded by her father.