Theresa May leads UK congratulations for Donald Trump
Theresa May has led UK political congratulations for Donald Trump after his US election victory.
The PM said Britain and the US had an "enduring and special relationship" and would remain close partners on trade, security and defence.
Labour's Jeremy Corbyn said an economic system that "isn't working for most people" had been rejected.
Scottish First Minister Nicola Sturgeon urged Mr Trump to "reach out" to those feeling "marginalised" by his campaign.
UKIP's Nigel Farage drew parallels with the Brexit campaign and said he would "hand over the mantle" to the Republican.
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In a statement issued by Downing Street, Mrs May - who had previously criticised some of Mr Trump's remarks - said: "I would like to congratulate Donald Trump on being elected the next president of the United States, following a hard-fought campaign.
"Britain and the United States have an enduring and special relationship based on the values of freedom, democracy and enterprise.
"We are, and will remain, strong and close partners on trade, security and defence.
"I look forward to working with President-elect Donald Trump, building on these ties to ensure the security and prosperity of our nations in the years ahead."
In December 2015 she criticised the Republican's call for a ban on Muslims entering the United States, saying it was "divisive, unhelpful and wrong".
At the time Mrs May, who was then home secretary, also said Mr Trump's remark that police were afraid to enter some parts of London because of radicalisation was "nonsense", saying: "I just think it shows he does not understand the UK and what happens in the UK."
Foreign Secretary Boris Johnson tweeted his congratulations to Mr Trump and said he was "much looking forward to working with his administration on global stability and prosperity".
Like Mrs May, he has previously attacked Mr Trump's comments about London, saying that "the only reason I wouldn't go to some parts of New York is the real risk of meeting Donald Trump".
Mr Corbyn said Mr Trump's victory was "a rejection of a failed economic consensus and a governing elite that has been seen not to have listened".
He added: "And the public anger that has propelled Donald Trump to office has been reflected in political upheavals across the world."
The Labour leader also said Mr Trump's campaign had been "nasty and divisive" and that he looked forward to "robust discussions" with the president-elect about climate change and the importance of the United Nations.
Ms Sturgeon congratulated Mr Trump but said his victory was not the outcome she had hoped for, adding: "I hope the president-elect will take the opportunity to reach out to those who felt marginalised by his campaign and make clear - in deeds as well as words - that he will be a president for everyone in modern, multicultural America."
Her predecessor Alex Salmond said Mr Trump - who has extensive business interests in Scotland - said the President-elect was a "protectionist" when it came to trade but he hoped that his views would change in the White House.
"The difficulty with Donald Trump is not when he's winning, it's when he's not getting his own way," he said.
"He's nice as nine pence when he's getting his own way. It's what happens when he reaches road blocks, obstacles, when somebody says no to him... In these circumstances we'd better all just hope that the Presidency changes a man."
Mr Trump was criticised by a number of UK MPs during the campaign, including during a Commons debate in January on banning him from the country.
As Westminster reacted to his victory, Lib Dem leader Tim Farron said the values of "moderation, freedom, respect for the rule of law, openness and concern for one another" had been defeated, while Green Party joint leader Caroline Lucas said it was "a devastating day".
However, Conservative MP Michael Fabricant highlighted Mr Trump's reported enthusiasm for a trade deal with the UK, comparing this with the outgoing president's "back of the queue" comment.
Mr Farage, who joined Mr Trump on stage during the campaign, congratulated him on his "brave" campaign.
"We now have a President who likes our country and understands our post-Brexit values," he said. "Voters across the Western world want nation state democracy, proper border controls and to be in charge of their own lives."
Steve Hilton, a former adviser to David Cameron in Downing Street, said the Republican tycoon won because Americans could see in him "someone who might make a difference to their lives".
Sir Peter Westmacott, who was UK Ambassador to the US until earlier this year, said Mr Trump had been a "law until himself" during the campaign and it was not clear who would form his foreign policy team.
While there were significant policy differences that would need to be "ironed out", he told BBC Radio 4's World at One that the UK's relationship with the US was strong and it was natural for Mrs May to want a "fresh start" following Trump's election.