Prince Charles ‘going through the motions’ alongside ‘uncomfortable’ Princess Diana at this key moment

It's been over 40 years since the engagement of Princess Diana to Prince Charles - but now a body language expert has revealed exactly how the couple felt during the official photo shoot.

• The late princess became engaged to Prince Charles on 24th February 1981
• The couple had been dating for six months before the news of the engagement
• In other royals news, The sweet bond that Kate Middleton believes only her and Prince Louis share

The marriage of Princess Diana and Prince Charles didn't last - but royal fans were ecstatic when the news was made official - that the young couple were engaged in February 1981.

The couple posed for photos outside Buckingham Palace, and now, 40 years on a body language expert reveals that Diana was feeling 'uncomfortable' and Prince Charles was just 'going through the motions'.

Body language expert Darren Stanton from Slingo says Princess Diana's body language, who will have her famous Panorama interview explored in the Crown, during the shoot shows just how nervous and uncomfortable she was.

He said, "Diana appears nervous and in some photos is seen with her arm positioned across her chest in what is known as a self-reassurance hug. This posture tends to be adopted by those that are feeling uncomfortable in their environment, suggesting Diana was nervous and quite intimidated by the level of attention she was receiving."

Prince Charles, who, along will Camilla will step in for the Queen at this major event, however, was more confident in the now iconic photos, "He was used to being in the public eye - but the expressions he is displaying in the photos don’t seem to be consistent with the emotions he is trying to convey. Instead, we can assume that Charles is just going through the motions because, unlike Diana, he was so used to having his photograph taken."

Princess Diana went on to marry Prince Charles five months later in a ceremony at St Paul's Cathedral - however, the marriage only lasted just over 10 years - officially separating in 1992 and divorcing in 1996 - due to their incompatibility.

Stanton believes the engagement photos already showed a worrying lack of emotion from Prince Charles, saying, "while he appears quite calm and seems comfortable, not surprisingly as they are in the grounds of Buckingham Palace, he lacks sincerity in his emotion - this is visible by his face failing to appear completely engaged - and there appears to be a disconnect between himself and Diana, as he is leaning away rather than in towards his fiancée.”

Prince Charles went on to marry Duchess Camilla, who found a chic way to keep cool in the UK heatwave recently, in April 2005.