Britain's finance minister Nadhim Zahawi, who is running to replace Prime Minister Boris Johnson, said on Monday he would publish his tax return annually if he becomes leader.
"I will publish my accounts annually. That's the right thing to do," Zahawi told Sky News, after newspapers reported his tax affairs were being investigated by the authorities.
He said neither he nor his wife had never benefited from an offshore trust, or had nom-domiciled tax status.
The leadership race to replace Johnson, who was forced to resign after a flurry of scandals surrounding his behaviour and that of his government, is set to be a hotly contested race.
11 candidates have put their hat in the ring for the top position, a number which is likely to rise by the end of the day if UK Home Secretary Priti Patel launches a campaign.
Tax is expected to be the defining issue of the race, with the majority of Tory candidates criticising the existing tax regime - which was instituted under the Conservatives who have been in power for over a decade.