Britain's ruling Conservative Party confirmed on Monday that 10 candidates will vie to succeed Prime Minister Theresa May as party leader, as several contenders launched their campaigns with pledges to deliver Brexit.

Frontrunner Boris Johnson, Foreign Secretary Jeremy Hunt, Environment Secretary Michael Gove and Home Secretary Sajid Javid are among those who will enter this week's first round of voting. The 313 Conservative members of Parliament will begin voting tomorrow. They will hold a series of secret ballots to whittle down the field to a final pair, who will be put forward to the around 160,000 party members from next week to choose Britain's next prime minister. Centrist Conservative Sam Gyimah said on Monday he was pulling out of the contest to replace May. Gyimah was the only candidate to support holding a second referendum on Brexit. The competition is dominated by Britain's looming EU exit on Oct. 31, with leading Brexiteer Boris Johnson, a former foreign secretary, among those talking tough on the need to renegotiate the divorce terms or leave without a deal.

May, who took office after the referendum, was forced to quit after failing repeatedly to get her EU divorce deal through Parliament and delaying Brexit twice in the process. Brussels says it will not renegotiate the terms, which cover Britain's financial settlement, the rights of EU citizens and the Northern Irish border. But many of the leadership candidates insist they will try.

Johnson received praise from U.S. President Donald Trump for threatening to walk away with no deal at all. But he drew a rebuke from Paris on Sunday for saying Britain may withhold the multibillion-euro divorce payment, which May had agreed to pay, which covers its liabilities from four decades of EU membership.