Norway's King Harald has been admitted to a hospital in Oslo experiencing fatigue, paleness, and shortness of breath, the Royal Palace announced Monday. The monarch, Europe's longest-serving hereditary ruler, is 89 years old.

King Harald has been undergoing treatment for hemolytic anemia in recent weeks, a condition that causes red blood cells to be destroyed at an abnormally rapid rate. According to the palace, this has led to fluid accumulation in his body requiring hospitalization. He will be on sick leave for the next two weeks, during which time Crown Prince Harald will serve as Regent.

This is not the first health concern for the King in recent months. He had a planned check-up just 10 days prior to this admission. In February, he was hospitalized in Tenerife for an infection and dehydration, at which time his condition was reported as satisfactory. Two years ago, while on holiday in Malaysia, he had a pacemaker fitted after a similar health incident.

Despite his recurring health issues, King Harald has stated he has no intention of abdicating, citing a lifelong oath he took upon ascending the throne in 1991.

The royal family has also faced scrutiny regarding Crown Princess Mette-Marit's past ties to Jeffrey Epstein. The Crown Princess issued an apology after revelations of her staying at Epstein's mansion in 2013, and emails suggesting continued contact. King Harald previously defended his daughter-in-law, noting she had not acted illegally and had severed ties early.

Separately, Queen Sonja was hospitalized in Oslo's National Hospital earlier in the year due to heart problems, including heart fibrillation and heart failure. The 88-year-old Queen was later discharged and reported to be in better condition. She had a pacemaker fitted the previous year for cardiac fibrillation.