No information has yet come from the Norwegian court that the King's health has worsened.
The 89-year-old king was treated with cortisone in August for hemolytic anemia, a form of anemia. According to the court, this has led to fluid accumulation in the body that requires treatment in hospital.
This past weekend it was announced that King Harald's health condition had worsened.
"The King is receiving antibiotics for a bacterial infection in the blood, and has responded to this treatment," a press release said.
The latest update regarding the monarch's health came on Monday when the court announced that "there have been no significant changes in the king's health, and that the situation remains stable."
Crown Prince Haakon arrived at the National Hospital just before 4 p.m., Crown Princess Mette-Marit shortly afterwards in a car driven by Prince Sverre Magnus. Queen Sonja arrived about half an hour later.
In recent days, several other family members such as Princess Märtha Louise, the King's sister Princess Astrid and several of the grandchildren have visited the King.
Princess Märtha Louise's husband Durek Verrett is also currently being treated at Rikshospitalet, where he has undergone a kidney transplant.
