A day before the USA president was due to have bilateral talks with Theresa May, Trump used an interview with the Rupert Murdoch-owned Sun to endorse her principal Tory rival just days after he resigned from the cabinet in protest at her Brexit policy.
Britain's Prime Minister Theresa May and her husband Philip May greet Trump and First Lady Melania at Blenheim Palace.
"Theresa May has invited President Trump to our country at a time when his risky and inhumane policies are putting the lives and wellbeing of millions of people at risk", he said. Her husband, Philip, like President Trump, kept things basic in a traditional tuxedo. "We must show Trump and the Tories that we can and we will defeat the politics of division".
Trump said he would try to avoid the crowd in the capital during his four-day visit to the country.
Trump also said Europe is "losing its culture" because of immigration from the Middle East and Africa.
"The people voted to break it up (Britain's ties with the EU)", Trump said.
"I think it's a travesty of British values". Another 13 percent said they didn't know.
After the dinner, the Trumps will travel to the US ambassador's official residence, Winfield House in London's Regent's Park, where they will spend the night.
At a welcoming garden party, the Beatles track "We can work it out" played in the background.
"The spirit of friendship and cooperation between our countries, our leaders and our people, that most special of relationships, has a long and proud history", she said, adding that the United States was "not just the closest of allies but the dearest of friends".
But some 77 per cent of Britons have an unfavourable view of Trump, according to a poll by YouGov with 1,648 respondents.
Anti-Trump protesters lined the roadway leading to the palace near Oxford - but it's unlikely the Trumps even saw them. You have a mayor who has done a bad job in London.
Meanwhile Amnesty International unveiled a 15-metre banner on Vauxhall bridge opposite the US Embassy branding him a "Human Rights Nightmare".
Protesters are set to fly the Baby Trump blimp over Parliament on Friday when Trump will not be in town. She also said that it's an opportunity to strengthen cooperation on security.
In an explosive interview inside the US Embassy in Brussels ahead of his visit to the United Kingdom, the US President said the London Mayor has "done a very bad job on terrorism".
On Wednesday, the First Lady dressed in the "colour of peace" as she stepped out with French First Lady Brigitte Macron for the North Atlantic Treaty Organisation summit.
The Commander in Chief is due to travel north of the border on Friday to spend the weekend playing golf at his Turnberry resort in South Ayrshire.
Russian Federation has strongly denied the charge.
Trump, who has compared his own election to the June 2016 referendum in which a majority of British voters supported leaving the European Union, complained, "The deal she is striking is a much different deal than the one the people voted on". Tens of thousands, or more, are expected to participate.
Trump next heads to Windsor Castle for tea with the queen, as protesters stage a mass demonstration in London.