More than 1,000 protesters lined the streets of Blenheim Palace, Oxfordshire England, where Theresa May welcomed US President Donald Trump for dinner.
Anti-Trump protesters also showed their disdain outside the US ambassador's residence near Regent's Park.
Many Britons are opposed to Trump's trip, which is not the full state visit he was originally promised. A YouGov poll on Wednesday showed 77 per cent had an unfavourable opinion of the president and just 50 per cent thought his visit should go ahead.
"I think they like me a lot in the UK," Trump said in Brussels. "I think they agree with me on immigration. I'm very strong on immigration."
More than 60,000 people have signed up to demonstrate in London on Friday when protesters intend to fly a large balloon over parliament portraying Trump as an orange, snarling baby.
London mayor Sadiq Khan called for all gatherings to be "peaceful and good-spirited".
A campaign is also underway to get Green Day's 2004 hit American Idiot to the top of the UK Singles Chart.
