The King will make his first state visit as monarch by welcoming the President of South Africa to the UK.
The Prince and Princess of Wales will play a key role in the visitwhich includes a state banquet at Buckingham Palace.
William and Kate will greet each other President Cyril Ramaphosa and his wife, Tshepo Motsepe, on behalf of the King. They will then travel with the couple to the welcoming ceremony at Horse Guards Parade.
Two hundred horses and a thousand soldiers will take part in the military parade, with gun salutes fired from Green Park.
A procession of state carriages will carry the president, the king and the Queen Consort and the Prince and Princess of Wales to Buckingham Palace for a private lunch.
The King will then show the President an exhibition of items from the Royal Collection relating to South Africa.
The royal red carpet will be rolled out at the evening’s state banquet, with both the Queen Consort and the Princess of Wales expected to wear tiaras.
State visits are the ultimate diplomatic gift, and decisions about who gets invited are made by the Foreign Office.
They give the UK government the opportunity to promote and advance international relations.
However, this has a particular meaning for the King, since it is the first of his reign.
He will deliver a speech at the start of the banquet, and his words will be carefully chosen and the King could use this opportunity to discuss his vision for the Commonwealth.
It is also the first state visit to the UK since the pandemic, with the previous one coming in 2019 when the Queen hosted US President Donald Trump.
Throughout her reign, the Queen hosted 116 State Visits and was known for taking great personal interest in small details.
His last visit to South Africa was over a decade ago in 2010, when he hosted President Jacob Zuma.
President Ramaphosa is currently facing controversy at home, accused of covering up the alleged theft of $4m (£3.4m) in cash from his farm. The president denies any wrongdoing.
Don’t expect any mention of that. This visit will be used to announce new projects between South Africa and the UK.
Prime Minister Rishi Sunak said: “South Africa is already the UK’s biggest trading partner on the continent, and we have ambitious plans to boost 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 capitalize on shared opportunities, from trade and tourism to security and defence.”