May has said Trump's visit is an opportunity to boost trade links between the United States and the UK amid Britain leaving the European Union.
Most people, a number of whom said they worked at the embassy in London, were tight-lipped as they left a secured area in the park near the U.S. ambassador's residence, where Trump and his wife Melania will stay overnight.
"I don't know if that is what they voted for".
The poll conducted this week said 63 percent found Trump racist, and 74 percent said he was sexist.
Another man, who did not wish to give his name, said: "It was very complimentary to England and to the allies that we have, very positive".
Well, at least Melania Trump is spending her time in London - and maybe Donald Trump could take some learning from that. "We will facilitate lawful protest and we will uphold other people's rights as much as we can".
Activists inflate a giant balloon depicting US President Donald Trump as an orange baby in north London on July 10, 2018, ahead of a demonstration in London to coincide with the visit of the US president.
"But having a special relationship means that we expect the highest standards from each other, and it also means speaking out when we think the values we hold dear are under threat", he said.
But Brexit champion Nigel Farage predicted there would be a "real clash" on Brexit.
May has had to defend Trump's visit in the face of fiery criticism from opposition lawmakers.
He is due to leave Britain on Sunday for talks in Helsinki the following day with Russian President Vladimir Putin, whose government stands accused by May's of unleashing a lethal nerve agent in the city of Salisbury.
Considering Trump's comments yesterday referring to the United Kingdom as "in turmoil", it will remain to be seen whether he keeps his silence on the issue during his visit today. (The only president she didn't meet was, Lyndon B. Johnson.) She has invited far fewer of them to Windsor Castle-just Ronald Reagan, whom she rode horses with in 1982; George W. Bush in 2008; and Barack Obama in 2016, as Vanity Fair notes.
His "America First" policies, including the decision to pull the USA out of the Paris climate accord and the nuclear deal with Iran, also have brought him into conflict with Britain's leaders over substantive geopolitical issues.
May will host a black-tie dinner for Trump there, attended by senior ministers and about 100 business leaders, including from Blackstone group, Blackrock, Diageo, McLaren and Arup.
U.S. Ambassador Woody Johnson said Wednesday that citizens are often advised to avoid public demonstrations and that he is not upset by the decision to allow the "Trump baby" balloon to be displayed near Parliament.