Queen Camilla thanked Novak Djokovic for allowing her to stay at his property in Montenegro

A video of the duo meeting at the All England Club shows the 38-year-old tennis star telling the Queen: "Oh yes, the property in Montenegro. Wonderful. I hope you enjoyed it."

Camilla, who was joined at Wimbledon by her sister Annabel Elliot, replied: "Lovely. It was quite a long time ago. Very nice."

The Queen also told Djokovic that she had her "fingers crossed" for his match against Italian player Flavio Cobolli, in which the former world number one prevailed in four sets.

Djokovic was asked about his conversation with Camilla after the match but he refused to elaborate on their "private" chat.

The 24-time Grand Slam champion said: "I prefer not sharing that. It's private. We had a nice exchange. I was actually surprised with her comment and a question that she asked. It was non-tennis related.

"She was very pleasant. Very, very pleasant. Of course, it's a great honour and privilege for me to be able to shake hands with the Queen of England."

Camilla and her husband - the then Prince Charles - completed a six-day tour of the Balkans back in 2016 where Camilla visited a children's home funded in the Serbian capital Belgrade funded by Djokovic's foundation.

The tennis icon responded by posting a video message on social media describing the royal's presence as of "tremendous importance and significance".

Meanwhile, it was revealed recently that the Queen will have a starring role in the new crime novel The Hawk is Dead.

Camilla is an avid reader and is a big fan of Peter James' Detective Superintendent Roy Grace thrillers and the latest story will take the character's investigation to Buckingham Palace when the royal train which Camilla is travelling on derails and a key member of her staff is shot by a sniper.

A source told MailOnline: "Opening with a cinematic derailment of the royal train, The Hawk is Dead takes Roy Grace deep into the heart of Buckingham Palace, where he is called upon to solve a murder and what looks to be a royal assassination attempt.

"Queen Camilla, a well-known book-lover and reading champion through her charity, The Queen's Reading Room, has always been one of the first people to receive each Grace novel and is excited to have a starring role, alongside His Majesty King Charles, in Peter's latest thriller."