LONDON — The diplomatic red carpet will be rolled out for a state visit by the Emir of Qatar, with the King and the Prince and Princess of Wales delivering a royal welcome on Tuesday morning.

But Queen Camilla still has a lingering chest infection and will miss the start, while Catherine's involvement in the visit by the Gulf state marks another step in her return to official duties.

The state visit's exercise in soft power will see the visiting Qatari royals given a carriage procession along The Mall, a visit to the Houses of Parliament and a banquet at Buckingham Palace.

Queen Camilla, who is said to have "diminished reserves of energy" after a chest infection, will miss the outdoor parts of the reception on Horse Guards Parade and along the Mall, but will attend events in Buckingham Palace later in the day, including the state banquet.

State visits are a mix of elaborate ceremony and practical politics, offering hospitality on a grand scale to an important international partner.

The visit to the UK by Emir Tamim bin Hamad Al Thani and Sheikha Jawaher bint Hamad bin Suhaim Al Thani began on Monday in damp weather at Stansted airport.

But over the next two days, there will be a carefully choreographed effort by the UK government to build warm relations with Qatar, from the pageantry of marching bands to a meeting with Prime Minister Sir Keir Starmer.

The Qatari visitors are from a Muslim country but it won't be an alcohol-free banquet at the palace, with both alcoholic and non-alcoholic drinks being served.

The UK Foreign Office, which advises on which countries are invited for a state visit, says Qatar is a key defense partner and that trade between the UK and the gas-rich Gulf state is worth £6.6bn per year, with £40bn of Qatari investment in the UK economy.

Qatar has been a mediator in talks over the conflict in Gaza, though the role was suspended last month.

And the country's Emir has been a regular visitor to the UK, coming here at least eight times in the past decade. He studied at school in the UK and attended Sandhurst military academy.

The Qatari royals will receive a ceremonial reception and military inspection, followed by a carriage parade to Buckingham Palace.

The Princess of Wales will be part of the horse-drawn procession, taking part in a state visit for the first time since ending the chemotherapy treatment that followed her cancer diagnosis.

She will join a private lunch at the Palace, along with the King, Queen and other senior royals.

The Qatari visitors will be brought to Westminster Abbey and the Houses of Parliament, where the Emir will speak to representatives of the House of Commons and House of Lords.

The centrepiece of such state visits is the state banquet, where the King and Emir will give speeches in front of dignitaries from both countries, in the grand setting of the Buckingham Palace ballroom.

The Princess of Wales won't be at the banquet but it will be the first time Sir Keir will have been at this diplomatic showcase as prime minister.

A Foreign Office spokesman said: "Our strong, historic ties with Qatar are vital to UK prosperity, growth and security. The UK government is committed to continued strong relations with Qatar to deliver partnerships of mutual value." — BBC