Up to 45,000 demonstrators have descended on the capital today with other rallies in Manchester, Sheffield, Norwich, Windsor, Plymouth and Birmingham
ANTI-Donald Trump protesters have clashed with his supporters as tens of thousands marched through London today.
Crowds chanted "shame on you" and waved "dump Trump" banners during a mass demonstration in the capital this afternoon.
Police were forced to step in as protesters clashed with Trump supporters near a packed Trafalgar Square.
Jeremy Corbyn, Ed Miliband and David Lammy were among up to 45,000 people to join the march through the capital's streets.
The Labour leader told the assembled protesters Mrs May shouldn't have "rolled out the red carpet" for the leader of the free world.
Corbyn cited Mr Trump's jibes about the NHS and London's crime levels in his speech against the president.
However many Tory MPs and fans of The Donald on Twitter pointed out that he had previously invited the IRA to Parliament and called Hamas his "friends".
Celebrities including Bianca Jagger, Stephen Fry and actress Samantha Bond were also spotted at the event.
Police told The Sun they had made six arrests during the protests including one for assaulting a police officer.
Protests are also taking place in Windsor, Manchester, Sheffield, Norwich, Plymouth and Birmingham today.
Earlier a 20ft Trump baby blimp was inflated outside the House of Commons after London Mayor Sadiq Khan gave permission.
Mr Trump had earlier dismissed the stunt in his explosive Brexit interview with The Sun, saying: "I guess when they put out blimps to make me feel unwelcome, no reason for me to go to London."
The President added: "I used to love London as a city. But when they make you feel unwelcome, why would I stay there?"
Up to 200,000 demonstrators were expected to turn out for London's "Together Against Trump" march by 2pm.
And the Metropolitan Police warned Trafalgar Square is close to capacity and officers may have to halt the rally.
It came as Mr Trump and Melania arrived at Windsor Castle to have tea with the Queen.
Earlier Theresa May held a lunchtime summit with the US President after he said she was wrecking Brexit.
The two leaders hosted a joint press conference at Chequers, the PM's country home, where Mr Trump lavished praise on Mrs May.
He said the US-UK relationship is currently at "the highest level of special" and spoke of his admiration for the PM.
And he shifted his stance on a possible post-Brexit trade deal - expressing optimism that America and Britain will be able to come to an agreement.
The President said: "Once the Brexit process is concluded and perhaps the UK has left the EU - I don't know what you're going to do, but whatever you're going to do is OK with me - just make sure you can trade with us, that's all that matters."
Meanwhile, Brits have backed Mr Trump over his astonishing Brexit blast.
A showed 51 per cent of people believe he was right to reveal his views on Britain leaving the EU.
And some 60 per cent of Brits say Mr Trump should meet Her Majesty.
Protesters gathered outside the BBC headquarters in Marylebone before setting off towards Trafalgar Square.
A wall of noise surged up Whitehall just before 2pm as thousands marched on Westminster.
Demonstrators blew whistles, banged cooking pots and chanted "shame on you"; as they reached Parliament Square.
They were met by the controversial Mr Trump baby blimp, reinflated after it earlier hovered above the capital for just two hours.
The huge caricature was carried aloft by a team of "babysitters" wearing red baseball caps mocking the president's "Make America Great Again" slogan.
Mid Sussex Tory MP Sir Nicholas Soames launched a scathing attack on the blimp as it hovered near the statue of his grandfather Sir Winston Churchill, branding it “utterly pathetic, pointless and graceless”.
Twitter users were equally unimpressed, with Nick Gee writing: "I assumed the #TrumpBabyBlimp was going to be the size of the Hindenburg. £16k for a party balloon.
"Hope they kept the receipt."
Others found the blimp a bit "embarrassing".
The "Women's March" and "Together Against Trump March" took place while Mr Trump was at Chequers for talks with Mrs May.
Student Nick Harris, 20, from Lancaster, turned out in support of the US President's first state visit.
He told the Sun Online: "I love America and I think it's important to show we support its President.
"He was democratically elected. Why should anybody say he shouldn't come?
"I just wanted to show some people welcome him to our country."
Corbyn, who was given a police escort, addressed crowds packed into a near capacity Trafalgar Square.
The Labour leader said: "We are asserting our right to demonstrate, our right to free speech."
"When we unite together with common objectives, we can all win.";
The President sat down with the PM this morning hours after The Sun's world exclusive saw say she wrecked Brexit and killed off any chance of a vital US trade deal.
After watching a joint US and UK military demonstration at Sandhurst army base Mr Trump took his official helicopter to Mrs May's country residence.
They later held a lunchtime summit after the American leader delivered a damning verdict on the Prime Minister’s EU negotiating strategy, just hours before he arrived in the UK.
Meanwhile the First Lady Melania Trump was on a joint visit the Royal Hospital Chelsea with the PM’s husband Philip May today.
After tea with the Queen, the First Couple flew up to Scotland for a private two-day visit, spending time over the weekend at his Turnberry golf resort in Ayrshire.
Anti-Trump protesters are also expected to stage demonstrations outside the plush course in South West Scotland and five-star resort in Balmedie, Aberdeenshire.
And some were there when his plane touched down in Scotland.
Mr Trump told The Sun during his Brussels visit earlier this week: “If they do a deal like that, we would be dealing with the European Union instead of dealing with the UK, so it will probably kill the deal.”
His comments were part of his most brutally honest verdict yet on Britain, in an interview with The Sun which also saw him:
Brexiteers and Remainers have interpreted the interview in a number of different ways, with Eurosceptic MPs saying Mr Trump's remarks should kill off the PM's Chequers plan.
But pro-EU politicians insisted the comments prove Brexit is a mistake.
Jacob Rees-Mogg, chair of the European Research Group, added: "The UK wants to do a trade deal with Donald Trump, and he said if you want to do a trade deal with the United States this isn't the way to do it."
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