He added: "I used to love London as a city -I haven't been there in a long time". Tens of thousands, or more, are expected to participate.
But it's not simply the protesters, who are expected to dog Mr. Trump throughout his visit, including his weekend in Scotland, but his fraught relationship with political leaders accustomed to harmonious exchanges with USA leaders, a tradition of unity that goes back at least to the vital World War II partnership of Franklin D. Roosevelt and Winston Churchill.
On Friday, May and Trump will hold talks on Brexit, relations with Russian Federation, and trade ties at the prime minister's Chequers country residence, followed by a press conference.
A few hundred people gathered to watch the blimp launch in Parliament Square, with organizers of the stunt wearing red boiler suits and red baseball caps emblazoned with "TRUMP BABYSITTER".
'This isn't just about mocking him.
Trump had already cast doubt on May's Brexit plans earlier in the day after a North Atlantic Treaty Organisation summit in Brussels, where he provoked a crisis session to force allies to raise their defence spending. "Whatever Sadiq Khan thinks about Donald Trump, he should not put that personal enmity above the fact that President Trump is the leader of the biggest and most important country in the world". "We got what we came for, and our special relationship is still very special".
The US president's brash style and hardline "America First" policies have caused consternation across Britain's political spectrum and society. Both of those accords were the result of years of painstaking diplomacy by European leaders - and Trump unilaterally trashed them.
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Friedland, who is white, later repeated the word with human resources staff trying to address the original incident, Netflix said. For the first three months of this year, the chain said a key sales figure fell 5.3 per cent in North America.
More than 64,000 people have signed up to demonstrate in London against Trump's visit while other protests are expected around the country. The issue is, "Do they have freedom to protest, freedom to assemble and should they be allowed to do so?"
According to his itinerary at this point, his only formal event in London - where his unpopularity is high - is a closed press meet and greet at the USA embassy on Thursday.
Melania Trump pulled out all the stops for her first night in the UK.
Although this is Trump's first official trip to the United Kingdom, he has been invited before.
He cast doubts on whether the Prime Minister was delivering what the British people had voted for in the European Union referendum.
But the sheer showmanship of the Trump baby has captured the public imagination. It was an extraordinary rebuke from a close ally.
May's Brexit plan "will definitely affect trade with the United States, unfortunately in a negative way", said the U.S. president. All of this controversy gives him energy, so he enjoys that'.
He and the first lady will also travel to Windsor Castle for tea with Queen Elizabeth.