The main order of business on Friday for Mr. Trump is a private conversation and working lunch with Mrs. May, who dearly wants to strike a trade deal with the United States as she tries to negotiate Britain’s departure from the European Union.
But Mr. Trump’s interview with The Sun, published Thursday night, overshadowed the meeting and threw some cold water on the prime minister’s hopes.
If Mrs. May persists in seeking a so-called soft exit from the European Union, Mr. Trump reportedly told The Sun, she can forget about a separate pact with the United States.
“If they do that,” the paper quoted him as saying, “then their trade deal with the U.S. will probably not be made.”
Hours before the interview was published, Mr. Trump was asked about Brexit at a news conference and said, “It’s not for me to say about the U.K.”
But speaking to The Sun, he described the prime minister’s approach to Brexit as “very unfortunate,” and said, “I actually told Theresa May how to do it, but she didn’t listen to me.”
He had much warmer words for Boris Johnson, the ambitious British politician who just quit as foreign minister in an open break with Mrs. May, and is seen as one of her primary rivals within the Conservative Party. Mr. Johnson, he said, would “make a great prime minister.”
At the very least, the interview gave Mr. Trump and Mrs. May some things to talk about on Friday.
The snarling baby takes flight
The most anticipated element of Britain’s “Stop Trump” protests, a giant orange balloon of President Trump depicted as a pouting baby in a diaper with a smartphone, took off Friday morning from Parliament Square.
Though the actual protest was still hours away, dozens of excited people gathered for the takeoff, including activists, tourists, children and bystanders diverted from their commute to work. They gathered around the balloon and, as if it were a rocket launch, counted down from 10 before setting it into motion.
“This is a victory,” said Leo Murray, an activist and the creator of the balloon. “People love it, he hates it and it’s driven him out of London.”
Mr. Murray and others behind the inflatable “ Trump Baby” have called the balloon a “symbol of resistance” aimed at giving Mr. Trump a clear message that he is not welcome in Britain.
“The only way to get through to him is to get down to his level and talk in a language he understands, one of personal insults,” Mr. Murray said.
Tens of thousands of protesters are expected for a 2 p.m. demonstration against Mr. Trump’s policies.
Adam Cottrell, one of the protest organizers, said, “He mocks and insults anyone who doesn’t support him so now he can see what it feels like.”
But Lucy Lawson, an American expatriate who came to see the balloon because of its proximity to her work, said that she opposed Mr. Trump’s policies, but considered the protest childish.
“Why are people going down to his level?” she asked. “Why are they being so childish? It’s because of his childlike leadership that we are in this mess.”
Ms. Lawson asked one of the organizers why they still decided to launch the balloon, knowing that Mr. Trump would not be in London.
“It’s going to swamp his twitter feed,” Mr. Cottrell said. “There’s no way he doesn’t see this.”
The Sun finds itself at the center of the journalism universe
British newspapers, especially the tabloids, know a good story when they see one, and the release of President Trump’s interview with The Sun dominated the front pages. A sampling of the headlines:
The Sun, which is owned by Rupert Murdoch’s News Corp., proclaimed under a banner trumpeting the interview, “May has wrecked Brexit … deal is off!”
The Times of London, which is also owned by News Corp. but generally takes a more restrained approach, said, “Trump: May’s soft Brexit will kill chance of US trade deal.”
The Daily Mail described it as the “President’s Brexit Attack on May,” while another tabloid, the Daily Mirror, took a briefer approach that nonetheless managed to make its point: “Donald Thump.”
The Guardian has compiled a roundup of the pages here.