OSLO, Norway: Norway's Crown Princess Mette-Marit has been put on a waiting list for a lung transplant after her health got worse, the royal palace said on May 5.

The 52-year-old wife of Crown Prince Haakon, who will be Norway's future king, was diagnosed in 2018 with pulmonary fibrosis, a long-term illness that scars the lungs and reduces oxygen intake.

The palace said that because her condition is serious and life-threatening, and after detailed medical checks, she has now been added to the transplant list.

Oslo University Hospital had said in December that the time for a transplant was getting close, though she was not on the list at that time.

Earlier this week, Crown Prince Haakon ended his official visit to Japan early to return home, while their daughter, Princess Ingrid Alexandra, also came back to Oslo from Australia, where she is studying.

Doctors said her illness has worsened and that she will need a transplant as soon as possible.

Prime Minister Jonas Gahr Stoere praised her for speaking openly about her illness, saying it may help others with similar conditions.

The royal couple has also postponed their 25th wedding anniversary celebrations, which were planned for August.

Mette-Marit met Haakon in 1999 at a music festival when she was 25, a single mother, and not from a royal background. Their relationship initially sparked public controversy but later gained broad support among the Norwegian people.