Johnson said: "His mission is really to strengthen the special relationship".
From there he will travel to hold talks with the prime minister at her Chequers country retreat in Buckinghamshire on Friday, before meeting the Queen at Windsor Castle.
Mr. Trump and Ms.
"We always stand side by side with each other and is this the way you welcome a good friend?" she said.
"President Trump has locked up 2,000 little children in cages and is refusing to release them unless he is allowed to build a wall", opposition Labour lawmaker Gavin Shuker said to May in parliament last month.
But it seems he is unlikely to to see a giant balloon depicting him as an orange baby, which London Mayor Sadiq Khan - target of Twitter attacks by Mr Trump - has given protesters permission to fly in Westminster on Friday.
Asked whether Chequers had been chosen to avoid planned protests in London, the spokeswoman said this was not the case and the venue was better for "more informal meetings". "The president is simply trying to get as impactful a trip as he can get in a 24-hour period". The U.K. on Thursday called on the Kremlin to fill in further clues about the March attack-which Britain has blamed on Russian Federation but Moscow has denied-to help U.K. authorities keep members of the public safe.
Erika Miller, 36, who has dual British-U.S. citizenship after marrying a Briton, said the protests would have no impact on relations between the two countries.
Mr. Trump and Mrs. In January, Mr. Trump abruptly called off a planned visit to London because he wasn't happy with the deal the US made to move its embassy in the city.
The former ambassador told Tom Swarbrick that the visit takes an agenda "designed to appeal to what they think Donald Trump will like". May said he was wrong to share an anti-Islam video posted by an anti-immigrant group.
The plan is to stage a dinner with top British officials and business executives to talk about trade - in a bid to show Trump that the tariffs he has both imposed and threatened are not necessary.
Mr Johnson told reporters on a conference call Friday that the president's itinerary was not created to keep him away from protesters. May has also expressed interest in such an agreement, but any deal can't be finished until the United Kingdom withdraws from the European Union, expected in early 2019.
"I know the man doesn't drink but sure, we could make him a cup of tea".
On Friday evening, the Trumps will travel to Scotland, where the President owns two golf properties, Trump Turnberry and Trump Aberdeen. Mr. Trump has two golf courses in Scotland. In a crowdfunding request, they wrote that they want the balloon to shadow the president, "haunting the skies - and hopefully the dreams - of the stain on the office of President that is Donald Trump Senior".
-Jenny Gross contributed to this article.