Theresa May promised to build a “better Britain” and to make the UK’s EU exit a “success” after she was announced as the new Tory leader and soon-to-be PM.
Speaking outside Parliament, Mrs May said she was “honoured and humbled” to succeed David Cameron, after her only rival in the race withdrew on Monday.
Mr Cameron will tender his resignation to the Queen after PMQs on Wednesday.
Mr Cameron, who has been UK prime minister since 2010, decided to quit after the UK’s Brexit vote.
It follows another day of dramatic developments in the political world, when Andrea Leadsom unexpectedly quit the two-way Conservative leadership contest, saying she did not have the support to build “a strong and stable government”.
Her decision left Mrs May – the front runner – as the only candidate to take over leading the party and to therefore become prime minister.
On June 24, Cameron announced his decision to step down by October, after the UK voted to leave the European Union. Speaking outside 10 Downing Street, he said “fresh leadership” was needed. The PM had urged the country to vote Remain but was defeated by 52 per cent to 48 per cent despite London, Scotland and Northern Ireland backing staying in.
Flanked by his wife Samantha, the PM had announced that he had informed the Queen of his decision to remain in place for the short term and to then hand over to a new prime minister by the time of the Conservative conference in October.
But in a rather unexpected move, Cameron announced his decision to quit later in the week, on Monday.
Speaking outside 10 Downing Street yesterday, Cameron said he would offer his resignation to the Queen on Wednesday afternoon at Buckingham Palace.
Cameron’s decision to quit came shortly after Mrs May’s only rival, Mrs Andrea Leadsom, abruptly pulled out of the race.
Mrs May and Mrs Leadsom were due to contest a ballot of around 150,000 Conservative party members, with the result to be declared by September 9. But Mrs Leadsom unexpectedly withdrew on Monday, removing the need for a nine-week leadership contest.
Mrs May will become Britain’s second female prime minister after Margaret Thatcher and among PMs to emerge without a general election.
As the new PM, she will now be saddled with the task of steering UK’s withdrawal from the European Union.
Britain’s planned withdrawal has weakened the 28-nation bloc, created huge uncertainty over trade and investment, and shaken financial markets.
Mrs May’s victory means that the complex process of extricating Britain from the EU will be led by someone who favoured a vote to remain in last month’s membership referendum. She has said Britain needs time to work out its negotiating strategy and should not initiate formal divorce proceedings before the end of the year, but has also emphasised that ‘Brexit means Brexit’.
Last Monday, Mrs May comfortably won the first round of the contest to become the next Conservative leader.
The leadership contest was sparked by David Cameron’s decision to step down as prime minister.
The process of choosing a successor – and the new prime minister – began last on Monday, and 329 of the 330 Conservative MPs took part in a secret ballot.
The result was later announced by Graham Brady, chairman of the 1922 committee of backbench Tory MPs, with Mrs May securing a comfortable lead over her rivals. The results showed that Mrs May polled 165 or 50 per cent votes while energy minister Andrea Leadsom got 66 or 20 per cent, Justice Secretary Michael Gove, 48 or 15 per cent, Work and Pensions Secretary Stephen Crabb, 34 or 10 per cent and former Defence Secretary Liam Fox, 16 or 5 per cent.
Fox, who came last was eliminated while Crabb, with 34 votes, decided to drop out.
The new prime minister, who had campaigned strongly for a Remain victory, said “fresh leadership” was required as the UK negotiates its exit from the European Union.
In a brief statement outside No 10 yesterday, Cameron said Mrs Leadsom had made “absolutely the right decision” to stand aside and that he was “delighted” Mrs May, the home secretary, was to succeed him.
He said a “prolonged period of transition” was not necessary, and added: “So tomorrow I will chair my last cabinet meeting. On Wednesday I will attend the House of Commons for Prime Minister’s Questions.
“After that I expect to go the Palace and offer my resignation.”
The prime minister described Mrs May as “strong” and “competent” and said she was “more than able to provide the leadership” the UK needs in the coming years.
“She will have my full support,” he added.