"So we turned Madame Tussaud's into a giant USS John McCain baseball cap", the group said. His delegation, heavy on family members and staff hangers-on, also includes Treasury Secretary Steven Mnuchin and other officials focused on a trade package.
On Monday, the queen gave Trump a first edition of Winston Churchill's "The Second World War". The crowd chuckled as Trump pleaded with her to stay in office.
Hundreds of thousands protested against him during a trip past year and a blimp depicting Trump as a snarling, nappy-clad baby will fly outside Britain's parliament during the visit.
Organisers, who wore red jumpsuits and hats marked "Trump Babysitters" had earlier launched the orange inflatable Baby blimp, prompting huge cheers from onlookers.
Notwithstanding Britain's enduring alliance with the United States, some British voters see Mr Trump as crude, volatile and opposed to their values on issues ranging from global warming to his treatment of women.
In central London, thousands of protesters were expected to take part in a "Carnival of Resistance" later in the day to voice their opposition to the president.
"As the U.K. makes preparations to exit the European Union, the United States is committed to a phenomenal trade deal between the USA and the U.K.", Trump said Tuesday in London during a news conference with British Prime Minister Theresa May. It will be the new prime minister's responsibility to achieve Brexit and any bilateral trade deal with the U.S.
"I think we will have a very, very substantial trade deal". Trump told the Sunday Times in an interview that Britain should "walk away" from talks and refuse to pay a $49 billion U.S. divorce bill if it doesn't get better terms from the EU.
The meeting with business leaders at St. James' Palace will bring together 10 leading companies - five from the UK and five from the United States.
Just up the street, protesters leaders of Britain's political opposition will be joining demonstrators.
It appears that the massive "Trump Baby" balloon that anti-Trump protestors have pulled about various London neighborhoods visited by President Donald Trump has been "popped" by a Trump Supporter who self-identifies as "Based Amy".
Trump takes shots at London mayor Sadiq Khan, dotes on his doppelgänger Boris Johnson, and finds no vacancies at Buckingham Palace on his trip to the United Kingdom.
Things are likely to become more awkward on Tuesday when he meets May, who is in the final weeks of her premiership. Huawei denies it is, or could be, a vehicle for Chinese intelligence.
Trump also took the unusual step of saying that Conservative Party leadership candidate Boris Johnson would make an "excellent" leader for Britain.
The president returned to Winfield House after attending a breakfast roundtable with British Prime Minister Theresa May and business leaders.
Trump, meanwhile, noted during the joint news conference that he expects more North Atlantic Treaty Organisation member states to increase their defence budgets to 2 percent of GDP.
Britain is scheduled to leave the European Union on October 31, after pushing its original departure date back by several months because of a lack of agreement about what the deal should look like.
Some 13 candidates so far are jostling to replace her as prime minister by late July.