Updated at 1.30pm
US President Donald Trump arrived in Britain on Monday for a three-day state visit during which he is to attend a banquet hosted by Queen Elizabeth II and meet outgoing Prime Minister Theresa May.
On landing, Trump sent out a tweet calling London Mayor Sadiq Khan a "stone cold loser" for criticising Britain's decision to roll out the red carpet for the White House chief.
.@SadiqKhan, who by all accounts has done a terrible job as Mayor of London, has been foolishly “nasty” to the visiting President of the United States, by far the most important ally of the United Kingdom. He is a stone cold loser who should focus on crime in London, not me......
— Donald J. Trump (@realDonaldTrump) June 3, 2019
....Kahn reminds me very much of our very dumb and incompetent Mayor of NYC, de Blasio, who has also done a terrible job - only half his height. In any event, I look forward to being a great friend to the United Kingdom, and am looking very much forward to my visit. Landing now!
— Donald J. Trump (@realDonaldTrump) June 3, 2019
Trump and his wife are expected to stay at Winfield House, the US Ambassador’s official residence in Regent’s Park, but the Daily Mail and other British media are reporting that other members of his family will stay at the five-star Corinthia in Westminster, where they booked an entire floor.
Queen Elizabeth II welcomed Trump and his wife Melania to Buckingham Palace, where they are being treated to a guard of honour, a private lunch and a glittering state banquet.
The Queen officially welcomes President Trump to Buckingham Palace, with the sound of a gun salute in the background#TrumpUKVisit latest updates: https://t.co/4zaqzAiNZz pic.twitter.com/yG3bG7qAVz
— BBC Breaking News (@BBCBreaking) June 3, 2019
But beneath the pomp and ceremony, Britain is in turmoil with Prime Minister Theresa May due to step down within weeks over her handling of her country's exit from the European Union.
True to form, Trump ripped up the diplomatic rule book before he even touched down by saying former foreign minister Boris Johnson would make an "excellent" choice to succeed May.
He also recommended May's successor walk away from talks with Brussels, refuse to pay Britain's agreed divorce bill and leave the EU with no deal.
The much vaunted UK-US "special relationship" was already under strain over different approaches to Iran, China and the Paris climate change accord.
Opposition politicians are boycotting the banquet over what London's mayor Sadiq Khan called Trump's "divisive behaviour" and large protests are expected across the capital.
Banners created by UK based human rights organisation Amnesty International and unfurled over Vauxhall Bridge in central London.But May and Trump are expected to emphasise the wider benefits of the old alliance when they hold talks at Downing Street on Tuesday.
On Wednesday, they will join other world leaders in the English port of Portsmouth to commemorate 75 years since the D-Day landings, which changed the course of World War II.
"Our relationship has underpinned our countries' security and prosperity for many years, and will continue to do so for generations to come," May said ahead of the visit.
Trump's first official visit to Britain last year was overshadowed by criticism of May's approach to Brexit, as well as large demonstrations.
Protesters are planning another big turnout this week and are hoping to once again fly their inflatable balloon showing Trump as a baby over the streets of London.
But the president's itinerary, which also includes a tea with heir to the throne Prince Charles, will keep him away from the public.
He is not due to meet Prince Harry and his American wife Meghan Markle, who has previously been highly critical of Trump.
Asked about Markle's comments in his weekend interviews, Trump said: "What can I say? I didn't know that she was nasty."