UPDATE: Leadsom quits race to become next UK leader

UPDATED WITH LEADSOM QUOTES, MAY BACKGROUND, REWRITES THROUGHOUT

LONDON (AA) – Home Secretary Theresa May was set to become Britain’s next prime minister after her rival withdrew from the contest to lead the governing Conservative Party.

Junior Energy Minister Andrea Leadsom said she was quitting the race to succeed David Cameron because the country needed a new prime minister “as soon as possible” following Britain’s decision to leave the European Union.

A prominent campaigner for Britain to leave the EU, Leadsom had been expected to spend the summer trying to persuade party members to select her because the country needed a pro-Brexit prime minister to conduct exit negotiations with Brussels.

But speaking to reporters in central London on Monday afternoon, she endorsed Theresa May, who had supported a vote to remain inside the EU.

“A nine-week campaign at such a critical moment in our country is highly undesirable,” Leadsom said.

“Business needs certainty – a strong and unified government must move quickly to set out what an independent United Kingdom's framework for business looks like,” she added.

She continued: “The Conservative Party was elected only last year with a strong manifesto. We now need a new prime minister in place as soon as possible, committed to fulfilling that manifesto as well as implementing the clear instructions from the referendum.”

May was effectively confirmed as the U.K.’s prime minister-in-waiting after Conservative Party officials confirmed the leadership contest would not be re-run.

- Weekend of scrutiny -

Leadsom’s withdrawal came after a difficult weekend for her candidacy, in which a high-profile row broke out over comments she made about motherhood in an interview with The Times newspaper.

She appeared to suggest in the interview that, as a mother, she had an advantage in the race over May, who has no children.

Leadsom later clarified the remarks by saying “motherhood should not play a part in the campaign”.

May officially launched her own leadership campaign earlier on Monday morning, telling supporters that the country needed “strong, proven leadership to steer us through this time of economic and political uncertainty and to negotiate the best deal for Britain as we leave the EU and forge a new role for ourselves in the world”.

“Because Brexit means Brexit, and we're going to make a success of it,” she added.