Michael Gove. Photo/Telegraph

One of the leading contenders to replace Theresa May as Britains next prime minister has admitted to using cocaine two decades ago.

Environment Secretary Michael Gove, who is among the frontrunners to succeed May after she resigned as Conservative Party leader on Friday, said he regretted it.

About 20 years ago before I was married, I did take drugs, he told the Daily Mail, adding it happened on several occasions at social events.

It was something I deeply regret. Drugs damage lives it was a mistake.

The 51-year-old Tory MP said he was a young journalist when he decided to take cocaine, and that he had not envisaged going into politics at the time.

I look back and I think, I wish I hadnt done that. But I dont believe that past mistakes disqualify you, he added.

Obviously it will be for my colleagues in parliament and members of the Conservatives Party to decide now if I should be leader.

May stepped down as Conservative leader on Friday and formally triggered the race for a successor currently being contested by Gove and 10 other MPs but will remain prime minister until a new leader is chosen.

The leader of the party, which won the most seats at the last general election in 2017, automatically becomes prime minister.

The battle is expected to conclude by the end of next month, with former foreign secretary Boris Johnson the bookmakers favourite to emerge victorious.

Johnson, an ex-London mayor, has previously suggested he may also have tried to use cocaine, but later denied he had actually taken the drug.

Several other candidates, including current foreign minister Jeremy Hunt and ex-Brexit Secretary Dominic Raab, have owned up to using cannabis in their younger days.