Britain's Queen Elizabeth II laughs with US President Donald Trump during a state banquet at Buckingham Palace. —  AFP Photo

LONDON — US President Donald Trump meets outgoing Prime Minister Theresa May on Tuesday for trade-centred talks during his state visit to Britain, with protesters set to gather outside the gates.

After a glittering banquet thrown by Queen Elizabeth II on Monday, the second day of Trump's trip turns from pomp and ceremony to politics and business.

The president's three-day visit -- centred around Wednesday's D-Day 75th-anniversary commemorations -- comes at a tricky time for Britain, with May stepping down within weeks over her handling of Brexit.

The UK-US "special relationship" has been under strain over different approaches to Iran, the use of Chinese technology in 5G networks, climate change, and Trump's personal politics.

May is due to step down as leader of the governing Conservative Party on Friday, her Brexit strategy having imploded after nearly three years in the job.

Some 13 candidates so far are jostling to replace her as prime minister by late Jul y.

Trump has weighed in on Brexit, saying he would walk away from the European Union without a deal if he could not get a deal he liked.

He has also said he would like to strike a quick trade agreement once Britain leaves the EU.

"Big trade deal is possible once UK gets rid of the shackles," he tweeted Monday.

Trump and May are set to co-host a business breakfast meeting at St. James's P alace with five top companies each from Britain and the United States.

Chiefs from BAE Systems, GlaxoSmithKline, Barclays, Reckitt Benckiser, JP Morgan, Lockheed Martin and Goldman Sachs International are among those expected to attend.

Free trade deal

"It is a great partnership, but one I believe we can make greater still," May was to say at the business round-table, according to her Downing Street office.

"With a bilateral free trade agreement, with broader economic co-operation... there are opportunities to seize.

"Through dialogue like this we can ensure that our economic partnership not only endures but continues to grow stronger for many years to come."

Britain's Prince Andrew, finance minister Philip Hammond and international trade minister Liam Fox are set to take part, along with US Secretary of State Mike Pompeo and US Treasury Secretary Steven Mnuchin.

May, Trump and their teams were then set to hold talks at Downing Street, followed by lunch together and press conference.

State visits are filled with ceremony, personal touches, gifts and fancy dinners -- this one being no exception.

The three-course lunch in 10 Downing Street's state dining room will consist of Paignton harbour crab, followed by Lake District beef fillet and an Eton mess with peach for dessert.

May will give Trump a copy of one of the most significant documents in the transatlantic "special relationship" -- a framed copy of Winston Churchill's personal draft of the 1941 Atlantic Charter, which defined the Allied goals post-World War II.

Trump and May will also go on a private tour of the Churchill War Rooms, the bunkers from which Britain's wartime prime minister ran his operations. — AFP