Ashitha Nagesh and Nick Johnsonin London
BBC
Thousands have gathered in central London's Portland Place for a protest against US President Donald Trump's second state visit.
Organisers Stop Trump Coalition - a group of more than 50 unions and charities - started the march towards Whitehall at around 15:00 BST.
Some protesters carried signs with slogans written across them including "no to racism", "no to Trump" and "stop arming Israel".
Others carried smaller versions of the 20ft Trump Baby blimp that floated through crowds during protests against the president's first state visit in 2019.
More than 1,600 police officers have been deployed including 500 from other forces, the Metropolitan Police said.
The force's Deputy Assistant Commissioner, Louise Puddefoot, said it would be "another busy day" for officers. This protest comes just days after the Unite the Kingdom protest.
She added that police had been in "close contact" with the organisers and had asked all taking part to be "considerate to the local community" and keep disruption to a minimum.
The Stop Trump Coalition includes groups ranging from climate campaigners to anti-racism groups and pro-Palestine organisations.
Ahead of the march, a spokesperson for the coalition said: "A government that will bow down to Trump and to racism is one that will open the door to fascism."
Although Trump will not be visiting Parliament, the protest groups said they would demonstrate to "defeat the politics of Trumpism" and to promote "an alternative, democratic vision of the world based on peace, social justice and international cooperation".
In the midst of the crowds - which started gathering near BBC Broadcasting House - people told the BBC why they were there, racking up a long list of grievances against the US president. They said they found him "despicable" and wanted to send a message that he is not welcome.
Reverend Poppy Hughes, who was asked about those who say vicars should be apolitical, replied: "Jesus preached peace and compassion and that's why I'm here".
Reverend Poppy Hughes came because of the teachings of Jesus
Zoe Gardner, a political commentator and one of the organisers of Wednesday's protest, said that Trump "represents everything that we hate".
"We want our government to show some backbone, and have a little bit of pride and represent that huge feeling of disgust at Donald Trump's politics in the UK," she added.
Climate campaigner Auriel Dowty Glanville from Wimbledon said she was demonstrating because she believes the president is a "climate denier" and climate change "is the biggest threat facing us on Earth".
She called the second state visit invite "appalling", adding: "It's all about the trade deal."
Auriel Dowty Glanville has dressed up with her take on the Statue of Liberty for the protest
Sarah Montgomery and Claudio Solano, from North London, arrived in white protective face masks that read "Trump stinks".
They said they have had the masks since Trump's first state visit.
"He still stinks," Sarah says. "Everything he stands for stinks."
Mr Solano, from Brazil, said he disagrees with both Trump's policies and his support for Brazil's former right-wing leader Jair Bolsonaro.
"It is disgusting, and I don't understand why Britain has to be so cowardly," he added.
A small crowd of protesters also began to gather in Windsor on Wednesday afternoon, where Trump is spending the day with the Royal Family ahead of the state banquet.
Amy Tisi told the BBC she protested the last time Trump visited and is is "important to make a stand". She said she questioned if the "size and scale" of the trip were meant to fuel his ego.
Four men were arrested after images of the president and late convicted paedophile financier Jeffrey Epstein were projected on to Windsor Castle on Tuesday as Trump arrived in the UK.
Also in Windsor on Wednesday, a man wearing a Davy Crockett hat said Trump was "the greatest president". His remark was met with a chorus of boos from parts of the crowd.
Additional reporting by Alex Smith in Windsor