The US president and his wife Melania arrived in London on Thursday with the first official engagement of their two-day visit being a lavish black-tie welcome dinner at Blenheim Palace hosted by the British prime minister.
He is taking helicopters to his various destinations.
US President Donald Trump (C) gestures as he poses alongside Britain's Prime Minister Theresa May (2R) and Iceland's Prime Minister Katrín Jakobsdóttir (R) during the opening ceremony of the NATO (North Atlantic Treaty Organization) summit, at the NATO headquarters in Brussels, on July 11, 2018.
British Prime Minister Theresa May greets U.S. president Donald Trump at Chequers.
White House spokeswoman Sarah Sanders later told reporters Trump was "thankful for the wonderful welcome" he received in Britain. On Friday he travels to Windsor Castle, about 22 miles west of London, to meet with Queen Elizabeth II.
On Friday, Trump will meet with the prime minister and the Queen and then spend the weekend at one of his private golf courses in Scotland.
Trump, however, is the most unconventional of modern US presidents and there is some anxiety in Britain about whether he will adhere to protocol.
In a statement ahead of Trump's arrival, she said the visit would focus on trade and strengthening defence and security ties, saying there was no stronger alliance than Britain's "special relationship with the US".
He doesn't seem to admire the current British leader a great deal based on the interview he gave in Brussels at the end of a chaotic North Atlantic Treaty Organisation summit, to Britain's biggest selling tabloid.
Trump slammed the "soft Brexit plan" while speaking at a North Atlantic Treaty Organisation summit in Brussels yesterday, saying it is "not what people voted for".
Prime Minister Theresa May said her plan to keep close economic ties with the European Union once Britain leaves the bloc next March was "principled and pragmatic".
Trump also warned May in the interview that any future trade deal with Britain will not be likely if Britain has a soft exit from the European Union.
Speaking to the United Kingdom tabloid The Sun, Trump said a potential trade deal would "most likely" fail if May's strategy was implemented because the USA would be "dealing with the European Union instead of dealing with the UK".
The US leader had claimed he doubted a US-UK trade deal would happen because of Theresa May's Brexit plans.
The Sun said its interview with Trump was conducted in Brussels, where the North Atlantic Treaty Organisation summit was held earlier in the week.
"The president likes and respects Prime Minister May very much", she said.
"I think it changed the fabric of Europe, and unless you act very quickly, it's never going to be what it was, and I don't mean that in a positive way".
May's plan for the U.K.'s exit from the European Union is widely seen as describing a "soft Brexit", in that it would see the United Kingdom stay aligned with some European rules in order to maintain the free movement of goods.
It comes hours after Trump used a newspaper interview to launch an extraordinary attack on Mrs May's Brexit deal, before accusing Mr Khan of doing a "terrible job" in City Hall. I think your mayor has done a awful job, but when they make you feel unwelcome, why would I stay there?