Queen Camilla makes her first royal engagement since King Charles' cancer diagnosis was announced during a charity concert at Salisbury Cathedral

The Queen tonight made her first public appearance since her husband's cancer diagnosis was made public, assuring well-wishers that he was 'doing extremely well under the circumstances'.

Camilla, 76, was speaking as she arrived at Salisbury Cathedral in Wiltshire for a charity musical evening.

Ben Abbott, 40, from Wiltshire Air Ambulance, asked her: 'I hope HM is doing well, ma'am.'

Her Majesty replied: “He is doing extremely well, considering the circumstances. He is very touched by all the letters and messages that the public has sent from everywhere. That's very cheerful.'

The Queen had long been planned to attend the evening of music at Salisbury Cathedral to celebrate the work of three charities in Wiltshire and her husband traveled to Sandringham to attend.

She is a strong supporter of The Wiltshire Bobby Van Trust, The Wiltshire Air Ambulance and Community First, as well as the regiment's charities, the Grenadier Guards and The Rifles.

There was music from award-winning concert pianist Rupert Egerton-Smith and saw Her Majesty being greeted by a brass band and taken his seat after a reception.

The musical evening is in honor of Wiltshire Bobby Van Trust, Wiltshire Air Ambulance and Community First – Youth Action Wiltshire, as well as the regiment's charities, the Grenadier Guards and The Rifles.

It comes after it emerged Prince Harry may have switched flights to get home to Los Angeles faster after flying to London to see his cancer-stricken father.

The Duke of Sussex, who spent just 45 minutes with his father but did not see his brother Prince William at all, arrived at Heathrow Airport just before 2pm yesterday and is now back in LA where he will be reunited with his wife Meghan Markle.

Harry, 39, is said to have been seen leaving a Delta flight that landed at LAX airport at 6.16pm local time on Wednesday (2.16am Thursday UK time).

It's understood he switched to the Delta flight because the British Airways flight he was supposed to take was “delayed by two hours,” The Express reports.

Flight records show that the BA Flight 269 he was expected to take was scheduled to depart Heathrow at 3:05 p.m., but actually departed at 5:19 p.m.

Harry had flown more than 5,000 miles from Los Angeles to London after his father informed him of his devastating cancer diagnosis.

He flew to London on a 10-hour flight, arriving at Clarence House at 2.42pm on Tuesday before spending around 45 minutes with Charles.

They held a 'brief meeting' before the king and Camilla were driven to Buckingham Palace, where a helicopter waited to take them back to Sandringham in Norfolk.

It is believed the Duke has not seen his brother William or sister-in-law Kate Middleton, who is recovering from abdominal surgery and on extended leave.

As she waited for the Duke to return home, Meghan was photographed yesterday smiling as she drove around near the couple's home in Montecito.

Royal expert Jennie Bond told MailOnline that Prince Harry's visit to Britain shows how deep the royal rift has actually become.

She claimed: 'William showed today that he has rejected Harry, that he doesn't want to know him, and that he probably doesn't even like him anymore. Harry is just not part of his life.

“That rift is so deep now, as evidenced by the fact that Harry is here and they don't meet, so deep that I really wonder if it can ever be repaired.”

And Robert Jobson told Mail+ that while Charles may have been touched by his “sweet boy's” gesture, it actually caused “some concern by 'taking it upon himself' to fly over uninvited.”

Charles, 75, was seen in public for the first time since his cancer diagnosis as he left his office at Clarence House after a brief reunion with Harry.

The meeting has raised hopes the couple can repair their troubled relationship after Harry publicly criticized the royal family for unconscious racism and complained about the way Meghan was treated by palace officials.

Harry and Meghan left their royal duties in 2020 and now live in California.

Although the Duke met his father, there was no meeting between estranged siblings William and Harry, who have had a fractured relationship for several years.

Last night the Prince of Wales spoke for the first time about the King's cancer diagnosis, as he expressed his gratitude to the public for their 'kind expressions of support'.

William's words of praise, delivered at a fundraising gala dinner, also recognized those wishing the Princess of Wales well as she recovers from a planned abdominal operation.

He told the guests, “It means a lot to all of us.”

The heir to the throne was back at work yesterday to support the king as his brother Harry left London.

William had taken time off to support his family following Kate's surgery on January 16, returning to public duties once her care and recovery had been arranged.

But his first day back on duty came as the royal family was dealing with the health concerns surrounding his father, the head of state whose reign will pass the 17-month mark on Thursday.

William delivered his pre-dinner speech at the event, which raised money for London's Air Ambulance Charity's new helicopter fleet, where guests included Hollywood star Tom Cruise and Arsenal football club manager Mikel Arteta.

The Prince said: “I would like to take this opportunity to also thank you for the kind expressions of support extended to Catherine and to my father, especially in recent days. It means a lot to all of us.

'It's fair to say that the last few weeks have had quite a medical focus so I thought I'd head to an air ambulance unit to get away from it all.'

Weekly audiences between the King and Rishi Sunak are expected to resume in person within two weeks of Charles' cancer diagnosis.

Downing Street and Buckingham Palace took the unusual step on Wednesday of confirming details of a telephone conversation between the two, in a bid to show the king was continuing with his duties.

The Prime Minister wished Charles well in a brief telephone conversation before the formal in-person audience resumes on February 21.

Kate left hospital last Monday and returned to Adelaide Cottage in Windsor to be reunited with her three children, but the 42-year-old future queen is not expected to resume her official duties until after Easter.