Queen Camilla's chest infection was a form of pneumonia

Queen Camilla revealed to guests at Buckingham Palace on Tuesday that her recent chest infection was a form of pneumonia.

The 77-year-old had skipped the morning's official welcome outdoors at Horse Guards Parade, on advice of doctors, before joining the proceedings at the palace.

It's understood doctors have advised more time to rest and recover fully as she battles post-viral fatigue, though the Queen no longer has pneumonia.

Watch the video above.

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She contracted the illness after her tour to Australia and Samoa with King Charles and was forced to skip a number of big events last month, including Remembrance Day events, the Gladiator II charity premiere and the Royal Variety Performance.

Her Majesty is slowly returning to work following her illness based on doctor's advice.

As such, she arrived at Buckingham Palace shortly before the carriage procession returned from Horse Guards Parade, waiting inside the Grand Entrance to welcome the Emir of Qatar and his wife to the UK.

Queen Camilla joined the King for lunch with Sheikh Tamim bin Hamad Al Thani and wife Sheikha Jawaher bint Hamad bin Suhaim Al Thani.

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Queen Camilla also joined guests after lunch to view a display of Qatari items from the Royal Collection, which also took place inside the palace.

Camilla, who wore a navy dress which matched her husband's suit, is understood to be attending the evening's state banquet alongside King Charles.

However, someone who won't be attending the state banquet will be the Princess of Wales.

While Kate joined husband Prince William in the official welcome of the Sheikh and Sheikha on Tuesday morning, it's understood her gradual return to work will mean she will skip the evening's event.

Kate attended the lunch and afternoon display as well at Buckingham Palace, alongside Prince William and UK Prime Minister Keir Starmer.

The state visit marks the second of the year and the fourth of King Charles III's reign so far, following South Africa, South Korea and Japan.

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