With British Prime Minister Theresa May having stepped down as Conservative Party leader on Friday, the race to be the United Kingdom's next leader began in earnest on Monday, with several of the main contenders launching their campaigns.

May will stay in 10 Downing Street until her successor has been chosen by the Conservative Party. An initial long-list of 11 candidates will be whittled down to a final two by the parliamentary party, and then party members nationwide will vote on who will be the next leader and succeed May as prime minister.

Former foreign secretary Boris Johnson, who last week received the endorsement of US President Donald Trump before May even left office, and Health Secretary Matt Hancock launched their campaigns on Monday, but both these events were overshadowed by the ongoing coverage of environment secretary and would-be leader Michael Gove.

On Saturday, the leadership race got off to the least likely of starts with a newspaper front page story that Gove admitted to having taken cocaine two decades ago.

Initially he said he believed the "mistake" should not be held against him in his bid to become prime minister, but in a BBC interview on Sunday he admitted he had been "fortunate" not to go to prison, saying he had taken it on "several occasions" but he "did not believe" it was a habit.

Johnson's main bid launch promise was to cut income tax bills for people earning more than 50,000 pounds ($63,000) a year, using the money which has currently been set aside for a no deal-Brexit at the end of October-something he has said he is willing to embrace-to raise the threshold of the 40 percent tax rate to 80,000 pounds.

Critics have pointed out that since April this year, the basic annual salary for a member of Parliament has been more than 79,000 pounds.

Labour Party deputy leader Tom Watson, in a tweet, noted that Johnson's proposal contrasted with the extra money he had pledged to make available for schools: "A derisory ￡50m extra a year for state school spending. Today it's 200 times that on tax cuts for the richest 8 percent. Is he blinkered by privilege, or simply couldn't give a damn about the rest of the country?"

Other candidates include Home Secretary Sajid Javid, Foreign Secretary Jeremy Hunt and former Brexit Secretary Dominic Raab. To enter the race to be the next leader, candidates must have the backing of at least eight members of Parliament. The cutoff point to enter the race was 5 pm on Monday.

The first two ballots are scheduled for Thursday and June 18, with up to five votes taking place, if required, until there are just two candidates left. A final result is due on July 22.