King Charles has hosted his first state visit since becoming monarch, welcoming South Africa's President Cyril Ramaphosa to Buckingham Palace.
The pair are said to have voiced their mutual respect and admiration for both the late Queen and Nelson Mandela during the first day of the leader's two-day trip.
National figures had gathered in the royal pavilion for the pageantry of the ceremonial welcome, with Prime Minister Rishi Sunak joined by senior members of the cabinet including Foreign Secretary James Cleverly and Home Secretary Suella Braverman, as well as the Lord Mayor of London, Nicholas Lyons, and the defence chiefs of staff.
As Mr Ramaphosa was greeted by the King, gun salutes were fired across London.
More than 1,000 soldiers and over 230 horses took part in the event.
When Mr Ramaphosa picked up a photograph of the Queen with former president Mr Mandela during a 1996 Buckingham Palace state banquet, he said: "This lovely picture," and agreed when the King replied: "You were lucky to have known both."
The Prince and Princess of Wales were part of events for the first time, travelling to Mr Ramaphosa's luxury hotel in central London and accompanying him to Horse Guards Parade.
The South African president, who has been head of his country's government since 2018, also visited Westminster Abbey and Parliament on the first day of his visit.
Mr Ramaphosa followed the tradition of laying a wreath at the Tomb of the Unknown Warrior in Westminster Abbey.
He also gave a speech at the House of Parliament attended by Commons Speaker Sir Lindsay Hoyle and other MPs and peers.
In his address, Mr Ramaphosa called for improved trade and investment links between the UK and South Africa to help his country deal with ongoing power cuts.
He also said he would ask Mr Sunak to increase the number of South African university students coming to to study for doctorates in the UK
He also said he would urge Mr Sunak to agree a three-fold increase in the number of South African university students coming to study for doctorates in the UK when they have lunch together at Number 10 tomorrow.
Later on Monday, Mr Ramaphosa attended a banquet hosted by the King at Buckingham Palace.
On the menu at the state banquet was grilled brill with wild mushrooms and truffles and sorrel sauce, ballotine of Windsor pheasant filled with artichokes, quince compote and port sauce, a selection of assorted chantenay carrots, kale with roasted butternut squash, braised fondant potatoes, iced vanilla parfait with caramelised apples and petit fours.
The start of the visit was marked by the prime minister announcing the UK and South Africa will join forces to "turbocharge infrastructure investment and economic growth together".
The next phase of the UK-South Africa Infrastructure Partnership is being launched on Tuesday, supporting South Africa's economic growth through major infrastructure developments and offering increased access to UK companies to projects worth up to £5.37 billion over the next three years, said Downing Street.
President Ramaphosa's two-day trip is part of attempts by the UK to boost its relations with its biggest trading partner in Africa.
His appearance marks the first state visit to the UK by a world leader since former US President Donald Trump and his wife Melania met the Queen in 2019.
State visits were stopped during the COVID pandemic.
Ahead of Mr Ramaphosa's visit, the PM said: "South Africa is already the UK's biggest trading partner on the continent, and we have ambitious plans to turbocharge infrastructure investment and economic growth together.
"I look forward to welcoming President Ramaphosa to London this week to discuss how we can deepen the partnership between our two great nations and capitalise on shared opportunities, from trade and tourism and security and defence."