"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".
The president and his wife Melania will then be guests of honour at a dinner for around 100 guests in the spectacular setting of Blenheim Palace in Oxfordshire.
May will meet at Chequers for a series of bilateral talks.
The evening will end with the Royal Regiment of Scotland "piping out" the president, who will then spend the night at the official residence of the American ambassador - Winfield House in Regent's Park, central London.
Verstappen claims he can still be a contender after Austria GP win
His stopped Mercedes triggered a virtual safety auto , and most of the field chose to make an early stop for new tyres. It was double points finish for Sauber - with Charles Leclerc finishing ninth and Marcus Ericsson taking tenth place.
Ambassador Woody Johnson said Mr Trump was simply trying to get as much impact as possible from his 24 hours in England on what he described as a "very important" visit which the president would use to strengthen the trans-Atlantic special relationship.
"Our armed forces have fought together for over a century and no two countries work closer together in defence co-operation and that element of the visit is a reflection of that".
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.
Trump arrives in Britain on Thursday after a North Atlantic Treaty Organisation summit in Belgium that could turn contentious over the USA leader's insistence that allies pay more for their defence and amid trade disputes between Washington and Europe.
"He would love to do a bilateral trade deal and he is really ready to step up on that the minute we get the go ahead to do it", Johnson said, adding that USA government agencies were already looking at how to put a deal together.
Without his overtake of Raikkonen, Verstappen never would've won
The next race will be held at Silverstone on July 8, 2018. 'Everyone in the team will feel a nervousness. I hope it is not a title decider, but I can't predict what is happening going forward.
"We need to see that the relationship isn't damaged after these protests", he said.
Mr. Trump's visit-days before he is set to meet with Russian President Vladimir Putin in Helsinki, Finland-comes amid escalating tensions between the United Kingdom and Russia following the collapse of two United Kingdom nationals who were exposed to the same Soviet-era nerve agent that poisoned a former double agent and his daughter earlier this year. In January, Mr. Trump abruptly called off a planned visit to London because he wasn't happy with the deal the USA made to move its embassy in the city.
But Sir Westmacott said that the visit will also send a message to the President and America that the British "have lots to offer" in terms of military capabilities. "He will get it done fast because I know it is a major priority for him", Johnson said.
Others are holding marches through the city and in Scotland - where President Trump owns golf courses. 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".
Getting it dead wrong: woman found alive in morgue fridge
In another frightening case earlier this year, a Spanish prisoner regained consciousness hours before an autopsy was carried out. In 2016 another road accident victim, from KwaZulu Natal, was declared dead, only to be found breathing the next day.
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