The health of Norway's King Harald V, 89, has deteriorated during the weekend while in hospital, the royal household says in a statement.
Harald, Europe's oldest current head of state, was hospitalised on Monday and was treated for anaemia.
"His Majesty the King's health deteriorated over the weekend. The King is receiving antibiotics for a bacterial infection in his blood, and has responded to this treatment," the palace said, while adding that his condition was stable.
Harald received treatment for a skin infection on one of his legs while on holiday in Spain's Canary Islands in February.
In February 2024, the king fell ill during a private holiday with Queen Sonja in Malaysia and received a temporary pacemaker there.
Harald returned aboard a medical airplane to Norway, where he was fitted with a permanent pacemaker.
Following that episode, the king said he would cut back on official engagements but ruled out abdication, insisting his oath as king is for life.
Harald has been Norway's monarch since 1991.
Australian Associated Press