Princess Mary forced to apologise in Instagram post: 'I made a mistake'

Crown Princess Mary of Denmark rarely if ever puts a foot wrong, but the Aussie-born royal has made a major mistake during a recent engagement.

Mary, 48, was visiting the Grenaa sea aquarium on Wednesday, her first official engagement since the northern European summer holidays and her first since the peak of the coronavirus pandemic.

It was as she was greeting one of the hosts at the aquarium that she completely forgot about coronavirus protocols and shook hands with the man.

The royal was forced to apologise on Instagram on Danish Royal Household account.

The apology, which was written in Danish, reads: "On land, at sea and in the air — we have to get used to wearing a mask. It is important that we all follow the health authorities' recommendations together," she captioned two photos of herself wearing face masks, translated from Danish.

"Yesterday I was in Grenaa for my first official visit after the summer holidays," she continued. "At sea and in the air it went fine, but on land I made a mistake and I unfortunately shook hands. It reminded me how important it is that we help each other live up to the recommendations. Stay safe and take care of each other."

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The Danish National Board of Health guidelines state the best way to stop the spread of the infection include washing your hands, using hand sanitiser, coughing and sneezing into your sleeve, no handshakes (Mary!), no kisses on the cheek and hugs, limiting all physical contact, cleaning homes and workplaces thoroughly and keeping your distance from others.

Face masks are recommended for those travelling, commuters on public transport, when spending time with people at higher risk of contracting the virus such as the elderly, at large gatherings and at places such as the hairdresser where social distancing isn't always possible.

As of 21 August 2020, there have been 16,056 confirmed cases of COVID-19 in Denmark and 621 deaths. 1666 are still infected.

Princess Mary visited the aquarium after being appointed President for the World Wildlife Foundation. During the visit she helped release 50 sea rays into the wild.

She even held a net filled with five thornback rays on the dock ahead of their release.

An Instagram post shared the same day explained the release of the sea stingrays "must create new knowledge for both researchers and fisherman, as the majority of the 13 Danish stingrays today are threatened with extinction".

Princess Mary's brother-in-law Prince Joachim falls into the high-risk category when it comes to COVID-19, having recently undergone brain surgery on July 24.

He is now at home and is expected to make a full recovery.