Donald Trump has joined world leaders at Buckingham Palace for a special reception hosted by the Queen to mark 70 years of the Nato alliance.
The US President mingled with Boris Johnson, the Prince of Wales and fellow heads of state on Tuesday evening, ahead of Wednesday's Nato summit in Watford.
Mr Trump and wife Melania were among the first to arrive as demonstrators marched to the royal residence in protest at the event.
Fellow guests, including Labour leader Jeremy Corbyn and Canadian president Justin Trudeau, were greeted warmly by Queen Elizabeth in the palace’s grand music room, before moving to the Throne Room for a group photo.
The monarch chatted warmly to female leaders and first ladies including Mrs Trump and German Chancellor Angela Merkel before mingling with the rest of the leaders and their wives.
Mr Trump could be seen speaking to French President Emmanuel Macron, hours after the two traded barbs at a heated press conference.
The royals were out in force for the event, including the Duchess of Cambridge, the Princess Royal, the Duke and Duchess of Gloucester and Princess Alexandra.
The Duke of Cambridge is away in the Middle East and the Duke and Duchess of Sussex are on a six-week break from royal engagements.
Outside, hundreds of protesters led by NHS workers and anti-war activists had gathered in Trafalgar Square before marching towards Buckingham Palace to protest against Nato and Mr Trump.
Many in the crowd held aloft placards bearing messages such as "No to Trump, No to War" and "Trump, Hands off our NHS".
Mr Trump received a ceremonial welcome and a banquet at Buckingham Palace during his state visit to the UK in June.
The American leader was met by tens of thousands of protesters in London before he attended a D-Day commemoration service in Portsmouth.
He later boasted about having "automatic chemistry" with the Queen, and praised her as a "spectacular woman".
Nato - the North Atlantic Treaty Organisation - was established in Washington on April 4, 1949.
It began as a 12-member alliance to counterbalance the growing military might of the Soviet Union and to keep the peace in post-war Europe.
The political and military alliance now has 29 member countries
