King Frederik and Queen Mary go on private holiday without their children

King Frederik and Queen Mary of Denmark have taken an abroad trip together, leaving their son Crown Prince Christian to act as regent.

The Danish royals reportedly left for their getaway on Saturday morning and are set to return to their duties on Tuesday. The Crown Prince of Denmark is the eldest of the monarch's four children, and he has already acted as regent several times when his parents have been out of the country on state visits.

© getty

The 18-year-old future King became the first in line to the Danish throne in January when his father King Frederik succeeded his mother Queen Margarethe.

Crown Prince Christian has been ticking off major milestones in recent months, after he graduated from Ordrup Gymnasium in Copenhagen in June, the same school that his sister Princess Isabella, 17, attends.

The royal teenagers have two younger siblings, 13-year-old twins Prince Vincent, who attends Tranegårdsskolen in Gentofte, while Princess Josephine moved to Kildegård Privatskole last summer.

© Martin Sylvest Andersen

Christian could be seen towering over his parents in sweet graduation snaps, and he was seen wearing a traditional Danish graduation hat, an accessory that marks the completion of his academic journey.

In Denmark, it is customary for family members to place this hat on the graduate’s head after their final exam, a practice that seems fitting for a future king who will one day wear a crown.

Christian's three siblings were also there to celebrate the special occasion, and the royal teenager is expected to continue his education at university in autumn.

The young hier ticked off another significant moment earlier this year, when he was gifted a car from his parents after passing his driving test. The royal was spotted arriving at Amalienborg Palace in a BMW X1 Sport model back in April.