Prince Harry is missing being part of the working Royal Family, with one expert claiming his true feelings are given away by one tell-tale sign.

The Duke of Sussex spent a few days back in the UK for a visit this week attending events for the Invictus Games, including a special 10th anniversary celebratory service at St Paul’s Cathedral.

Crowds gathered outside cheered the Prince on as he entered the cathedral, with shouts of “we love you Harry” being heard as he arrived at the service.

Royal expert Tom Quinn told The Mirror that the Duke’s appearance has made him realise what he is missing out on having given up royal duties – meeting the public.

He said: “The one part of being a working role that Harry really misses is the chance to meet the public – however insecure he feels as a royal, he has always felt totally secure as a celebrity.

“This has its origins in the fact that when he was a teenager, he had to employ a full-time secretary just to deal with his fan mail.”

He continued: “Harry always enjoyed royal walkabouts and the chance to meet an adoring public. And to some extent they still are adoring – outside St Paul’s for a short while as Harry shook hands and smiled for his fans, the crowd sang ‘we love you Harry’.”

No other senior members of the Royal Family were present at the Invictus service, however Harry was supported by his maternal aunt and uncle, Lady Jane Fellowes and Earl Spencer.

King Charles was instead at Buckingham Palace for a garden party, where he was joined by most of the rest of the Firm.

Harry has since been reunited with Meghan Markle, as the couple flew from Heathrow to Abuja overnight on Thursday for their visit to Nigeria.

Although Meghan chose not to come back to the UK with Harry for the Invictus service, she met him at the airport before they boarded the British Airways flight.

Mr Quinn explained that the more the Duke stays “isolated” at their home in California, “the more he will miss interacting with the public”.

He said: “The public may not have warmed to Meghan, but they always loved the sad, lonely boy who walked behind his mother’s coffin and they still see him as a sad lonely boy today.”

Today will see the start of the Sussexes engagements in Nigeria, with their itinerary being revealed on May 9 by the country’s Defence HQ during a press conference.

While in the West African country Harry and Meghan will watch a volleyball game, travel to military hospitals and meet with injured armed forces personnel and their families.