Queen Sonja of Norway has now been discharged from hospital after the 87-year-old Norwegian royal was admitted following "breathing difficulties". The palace has stated the royal has returned from Rikshospitalet, Oslo University Hospital, after the "situation has normalised".

The statement issued suggested the royal would be out of action from events and engagements. It read: "The Queen is on sick leave for the rest of the week."

Earlier this week, on Tuesday, she was transported by medical helicopter to hospital, as she was staying at the royal chalet in Sikkilsalen, where she was spending Easter weekend with Norway's head of state, King Harald.

It was announced by the royal house on April 21 (translated into English): "Her Majesty the Queen was admitted to the National Hospital this evening for examinations due to shortness of breath. The Queen was transported by air ambulance from the Prince's Cabin in Sikkilsdalen, where the Royal Couple spent the Easter holiday."

This latest hospitalisaton comes after Queen Sonja had a pacemaker installed in January after experiencing cardiac fibrillation, a rapid and irregular heartbeat. The procedure earlier this year was reportedly successful.

Before being hospitalized this week, the Queen had two engagements scheduled for April 24.

One was a visit to Oslo's Sofienberg Church, where she was set to be given a tour of the site to see how Spireverket is contributing to the work of transforming the church into a cultural center for children, youth and the neighborhood. The queen was then due later that day to attend the opening of the "AK Dolven. Amazon" exhibition at the National Museum. 

The hospitalisation comes after Sonja appeared to be in good health earlier this month as the royals welcomed the President of Iceland, Halla Tómasdóttir, and her husband Björn Skúlason for a state visit.

Also in attendance were Crown Prince Haakon and Crown Princess Mette-Marit, as well as their eldest daughter, Princess Ingrid Alexandra.

Queen Sonja has been married to King Harald V since August 1968. The couple share two children, Crown Prince Haakon and Princess Märtha Louise.

When her husband ascended the throne in 1991, Sonja became Norway's first Queen in 53 years. Harald has previously stated that he does not plan on abdicating.

He said: "I stand by what I have said all along, I have taken an oath to the Storting and it lasts for life."