It has been confirmed however that Trump will only very briefly visit London.
"It gives off the hint that this is an attempt to drive a wedge between the United States and UK, at a time the UK is leaving the European Union, it's forcing the UK back to closer ties with the European Union because they'll be pushed away from the USA", he said.
The Trumps will have left town the night before for Scotland, where the President owns two golf properties, Trump Turnberry and Trump Aberdeen.
The pro-Trump rally will breach the Public Order Act if it does not start at 1pm on Saturday at Temple Place, central London, and follow a route to Whitehall where it must end at 2pm, the Met said.
Hundreds of thousands of Britons are expected to take to the streets nationwideon Friday in opposition to Trump, who is scheduled to arrive in the U.K. Thursday evening.
USA ambassador to the UK, Woody Johnson, has said a deal will be "a major priority" for Trump, calling Brexit "a once-in-a-lifetime opportunity to change direction".
Winfield House is the only place where Trump will spend time in central London, where demonstrators are expected to gather in their tens of thousands for a march on Friday afternoon, hours after a giant "Trump baby" balloon is flown near the UK Parliament in an eye-catching stunt.
"We are confident that there will be huge demonstrations against Trump wherever he visits", said Chris Nineham, of the Stop the War Coalition, which is helping to stage the so-called "carnival of protest".
May will seek to put the diplomatic tensions behind her when she hosts Trump on Thursday for a black-tie dinner with business leaders at Blenheim Palace, the birthplace of World War II prime minister Winston Churchill.
He has also said he might speak to Boris Johnson, who quit as foreign secretary over May's plans.
She said that when the United Kingdom leaves the European Union (EU), "there will be no alliance more important in the years ahead".
Later, Trump will take tea with Queen Elizabeth II at Windsor Castle, a home to the royals for 1,000 years, part of a tour created to keep him away from protesters.
The organisers behind the blimp however, said they were just "poking fun" and "hope Trump sees it".
The two leaders will hold talks the following day at Chequers, the 16th-century manor house which is the prime minister's official country residence.
After the visit, Trump will decamp to Finland for a one-on-one with Russian President Vladimir Putin on July 16.
During the dinner the Countess of Wessex's Orchestra will perform "a series of classic British and American hits" and the Royal regiment of Scotland will "pipe the President out at the end".