One senior Labour politician has refused to play the diplomatic game with a powerful attack on Donald Trump as “vile and horrible”.

Dame Margaret Beckett, a former Foreign Secretary under Tony Blair, said the President-elect won the race to the White House by “lying through his teeth”.

“I’m a mixture of horrified and terrified. I suppose the horror is for today and the terror is for tomorrow,” she told Sky News.

A clearly furious Dame Margaret said there was a need to “tell the truth” because others – now he had been elected - would start “seeing the good in Donald Trump”.

Both Theresa May and Boris Johnson simply offered warm congratulations to the winner - despite condemning him less than a year ago when he called for a ban on Muslims.

But Dame Margaret said: “This is a vile and horrible man who has fought a vile and horrible campaign.

“I’m not just talking about the way he treated Hillary Clinton. Look at the way he treated his opponents in the Republican primaries - he insulted them, he sneered at them, he told lies about them, he insulted their families. This is a horrible man.”

The veteran MP said there was a chance that Mr Trump would suddenly reveal he was “this nice sweet person”, adding: “I’m sure we will all be hearing this in the next few days.”

She said: “I have a seen a lot of bluster, a lot of bombast, a lot of unpleasantness. He has appealed to the worst in everybody’s nature and brought it out and encouraged it

“This is a man who, when someone heckled at a rally, called on his supporters to beat him up. He called for Hillary Clinton to have her security guard taken away.

“He even insinuated that people who didn’t agree with her about gun control should perhaps think about shooting her. What kind of a man is that?”

In contrast, after rushing out a congratulatory statement, the Prime Minister sent Mr Trump a personal letter of support to reaffirm the “strong ties” between Britain and the US.

And Mr Johnson tweeted: “Congratulations to Donald Trump and much looking forward to working with his administration on global stability and prosperity.”