Why Queen Mary's teenage son will rule Denmark instead of her while King Frederick is out of the country

Prince Christian of Denmark is acting as head of state while his father, King Frederick X, is out of the country.

Frederik, 55, is currently in Poland on his first trip abroad as king, leaving his eldest son as head of government in his absence.

The 18-year-old will take on the role until his father returns to Denmark on Friday with possible duties including signing laws, public appearances and appointing or dismissing ministers.

As the king's eldest son, Christian is 'deputy regent' and the role of head of state falls to him in relation to Frederick's wife, Queen Mary.

If he is unable to fulfill his duties, the task will fall to Maria, then Prince Joachim and Princess Benedkeek.

Historian and royal expert Sebastian Olden-Jørgensen from the University of Copenhagen told the Danish publication BT the palace is run 'completely by the book'.

“After all, there is a hierarchy and an order of precedence in the Royal House and that is respected,” he said.

Christian rose through the ranks when Queen Margrethe abdicated the throne on January 14, leaving Frederick as her successor.

The three-day role is the first independent task the prince has taken on since the change of monarch.

Olden-Jørgensen said that if Christian has to sign a law while Frederik is away, he is not expected to doubt it.

“In principle and on paper he can refuse to sign a law, but that has not been an option at all for over a hundred years,” he explained.

As the king's eldest son, Christian is 'deputy regent' and the role of head of state falls to him in relation to Frederick's wife, Queen Mary

“We have a constitution and some laws, but we also have a political culture, and it is just as steadfast and says, among other things, that the regent signs what parliament has passed.”

The prince broke royal protocol when he turned 18 in October 2023 by not accepting his royal allowance and taking up a full-time job until he is 21, to focus on his education instead.

But the study break didn't last long.

The young heir's title changed to Crown Prince Christian of Denmark and it was reported that he now receives government funding.

“It is absolutely certain that he will get his own appanage when the law is presented, because with duties and tasks also comes a reward,” Olden-Jørgensen said.

'Then the question is how big it will be and how it will all be more closely organised.'

Before Frederick's proclamation, BT's head of entertainment, Fie West Madsen, predicted that Christian would receive a very general royal allowance with his added responsibilities.

The 18-year-old will take on the role until his father returns to Denmark on Friday with possible duties including signing laws, public appearances and appointing or dismissing ministers.

West Madsen estimated that he would receive about 9 million Danish krone, which is just under 2 million Australian dollars, to cover his expenses.

“He will have a very different role than otherwise planned, and we should also expect that appanage will follow, but how much or how little he has to take on depends entirely on what the Crown Prince couple wants,” she said.

Christian also became a member of the State Council when he turned 18, a role that Olden-Jørgensen 'cemented' when Frederick became king.

'It is customary for the heir apparent to sit on the council, so it is usually just a formality. It is much more important that he was pushed to the front as a public figure on his 18th birthday,” he told BT before the abdication.

'Now that the Crown Prince and Crown Princess are at the wheel, it is up to them how many tasks they want to give him. We have to wait and see, but it will certainly be a lot.'