However, earlier in the day, Barnier wrote on Twitter that Brexit negotiations should begin when the United Kingdom is "ready", since the election had thrown May's majority into disarray. The Conservative Party and Labour Party, who both support leaving the single market and scrapping free movement of people, hold 580 of the 650 seats. May had hoped that the polls would give her an enhanced mandate and strengthen her hand at forthcoming Brexit negotiations.
At the time of writing, it appears that the Conservatives have struck a non-formal deal with the Democratic Unionist Party (the largest Northern Irish party, which supports Brexit) to allow Theresa May to continue as prime minister in a minority government.
Just hours after her voice broke as she offered her first, shaky, 3 a.m. response to an election that would end with her Conservative Party losing its majority in Parliament, she was grim-faced and joyless as she stood in the midday sun in front of Downing Street and announced she would stay on as prime minister.
Trump, who was answering a shouted question from a reporter during an Oval Office photo opportunity, did not expand on his comment.
May had sought to capitalize on Britons' desire to quit the European Union and the perceived weakness of opposition Labour Party Leader Jeremy Corbyn.
"I don t believe personally that Theresa May will remain as our prime minister indefinitely".
But north of the border the Tories performed strongly under the leadership of Ruth Davidson, winning 12 new seats as the Scottish National Party lost ground. In 2010-15 they entered a coalition with the Conservatives, but were badly burned by the experience which damaged the party's reputation among voters.
Corbyn also said there's enough opposition in Parliament and in May's own party to topple the government. "The mandate she's got is: lost Conservative seats, lost votes, lost support and lost confidence", he said. Though the electorate appears to still favor some form of Brexit, the results of Thursday's vote ultimately undermine May as she prepares to take on hardened European Union negotiators in Brussels. "I'm afraid we ran a pretty terrible campaign", she said.
"What the country needs more than ever is certainty", she insisted.
Election 2017: the most SHOCKING result in recent history?
The far-right UK Independence Party (UKIP) is set for a washout with no MPs while the Liberal Democrats are set to win 14 and the Green Party one MP, according to the NOP/Ipos MORI poll for BBC/ITV/Sky channels.
"Five years of Conservative government, I just can't, I'm afraid, be a cheerleader for that particular outcome because this was an open goal for all of us".
Leading Brexit campaigner Nigel Farage said the result had put the whole future of Brexit at risk.
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