Norway's King Harald was hospitalised on Monday with an infection and is being treated with intravenous antibiotics, the royal household said in a statement.
The 85-year-old monarch was in a stable condition, it said.
The king has been Norway's ceremonial head of state since 1991.
(Reporting by Stine Jacobsen in Copenhagen and Terje Solsvik in Oslo, editing by Essi Lehto)