Norwegians have laid flowers in front of the palace in Oslo after the royal household said King Harald V’s condition in hospital had become “extremely serious”.

His wife, Queen Sonja, and his son, Crown Prince Haakon, cancelled royal engagements to be at his bedside at Oslo University Hospital with other members of the family.

They all stayed for several hours, and then during the evening Haakon was seen returning with Crown Princess Mette-Marit.

The 89-year-old has been in hospital for 10 days receiving treatment for a rare blood condition, haemolytic anaemia. Late on Thursday afternoon the palace issued an update to say his condition was unchanged.

Having been on the throne since 1991, King Harald is Europe’s oldest head of state.

Crown Prince Haakon, 53, the successor to the Norwegian throne, has been serving as regent while his father is on leave.

King Harald has been treated in recent weeks with cortisone for haemolytic anaemia, a condition that causes the number of red blood cells in the body to be reduced, and leads to fatigue and shortness of breath.

There was a sombre mood in Oslo as Norwegians followed the comings and goings of the royal family. Crowds milled around in Palace Square throughout the day as Norwegian public TV scrapped its schedule to cover the story.

Although no-one in the royal family spoke, the message was clear that it had become an important moment to visit the king.

Among those visiting the hospital were Crown Princess Mette-Marit who arrived with Haakon, as well as her son Marius Borg Høiby, who is under house arrest during his appeal against a conviction for rape.

King Harald’s sister, Princess Astrid, also visited the hospital, along with Haakon and Mette-Marit’s children Princess Ingrid Alexandra and Prince Sverre Magnus.

Prime Minister Jonas Gahr Støre cancelled a planned trip to Germany, where he was expected to meet Chancellor Friedrich Merz on Thursday.

“The whole nation is with us as we send warm thoughts to the king and the rest of the royal family,” he said in a statement.

The king has had multiple health problems in recent years which have forced him to scale back his royal duties.

He was fitted with a pacemaker in 2024 after falling ill on holiday in Malaysia.

The Norwegian royal family has already faced a challenging year in 2026.

Crown Princess Mette-Marit received a lung transplant in June after she had been diagnosed with a rare form of pulmonary fibrosis in 2018.

The transplant came two days after Høiby was sentenced to four years in prison after being convicted of two counts of rape. He had denied the most serious charges and is to appeal the sentence.

Høiby, 29, was four when his mother married Crown Prince Haakon and is not himself a royal figure.

Also earlier in the year, documents were released revealing Mette-Marit’s frequent contact with the late sex offender Jeffrey Epstein.

She later apologised to Norway’s king and queen for her three-year friendship with Epstein and admitted to “poor judgement”, adding in a national TV interview that she wished she had never met him.