Crown Princess Mette-Marit of Norway has stepped out looking stylish to attend a concert as she resumes her royal duties following a bout of illness. 

The 51-year-old was snapped arriving at a concert for the 50th anniversary of record label Kirkelig Kulturverksted in Oslo on Sunday evening.

She looked cheerful and radiant despite her recent health struggles and her son Marius Borg Høiby, 27, facing assault charges. 

Mette-Marit opted for a full-length cross-patterned blue coat over a chic pair of navy trousers and simple heels. 

She clutched a small embellished Prada handbag, kept her makeup minimal and wore her blonde locks down her shoulders. 

The appearance comes just days after Mette-Marit made a visit to the Army’s Engineer Battalion, where her daughter, Princess Ingrid Alexandra, has been serving, signalling the princess is in better health. 

Mette-Marit has been gradually returning to her official royal duties after she fell ill due to medicinal side effects associated with her chronic lung disease. 

In late October, the Norwegian Royal Court confirmed to Femail that she was taking some time off, saying: ‘H.K.H. The Crown Princess is on sick leave.

Crown Princess Mette-Marit of Norway looked cheerful and radiant as she arrived at a concert for the 50th anniversary of record label Kirkelig Kulturverksted in Oslo on Sunday

Crown Princess Mette-Marit of Norway looked cheerful and radiant as she arrived at a concert for the 50th anniversary of record label Kirkelig Kulturverksted in Oslo on Sunday

She is resuming her royal duties after taking sick leave for due to medicinal side effects associated with her chronic lung disease

She is resuming her royal duties after taking sick leave for due to medicinal side effects associated with her chronic lung disease

Mette-Marit opted for a full-length cross-patterned blue coat over a chic pair of navy trousers and simple heels

Mette-Marit opted for a full-length cross-patterned blue coat over a chic pair of navy trousers and simple heels

‘Due to side effects of the medication that Her Royal Highness is using for her chronic lung disease, she is on sick leave, initially for a week. Her official program during this period will be cancelled or postponed.’

Earlier that month, the court warned that Mette-Marit’s current course of treatment for pulmonary fibrosis may interfere with her planned duties over the coming weeks. 

The Crown Princess’s health condition was first made public in 2018, when it was revealed Mette-Marit had been diagnosed with pulmonary fibrosis or the thickening of lung tissue

At the time, Mette-Marit issued a statement explaining that the condition ‘means my working capacity will vary’ to accommodate her treatment including ‘periods of time without an official programme’.

‘For a number of years, I have had health challenges on a regular basis, and now we know more about what is involved,’ the mother-of-three said. ‘The condition means that my working capacity will vary.

Pulmonary fibrosis is incurable and worsens over time, but the Norwegian royal’s doctor, Professor Kristian Bjøro at the National Hospital, said they’d been monitoring her condition for several years and the ‘disease progression has been slow over this period’.

Not much is known about the unusual variant of fibrosis that was detected in Mette-Marit’s lungs but, according to the Royal House, ‘there is broad consensus that, unlike other more common types of pulmonary fibrosis, it is not related to environmental or lifestyle factors’.

The fact that the disease was detected at an early stage improves Mette-Marit’s prognosis, as per the Palace’s official statement.

She clutched a small embellished Prada handbag, kept her makeup minimal and wore her blonde locks down her shoulders

She clutched a small embellished Prada handbag, kept her makeup minimal and wore her blonde locks down her shoulders

Not long after announcing her absence, Mette-Marit had to step in for her husband Prince Haakon (right) at a state lunch as he reportedly had to escort her son Marius Borg Høiby (left) to rehab

Not long after announcing her absence, Mette-Marit had to step in for her husband Prince Haakon (right) at a state lunch as he reportedly had to escort her son Marius Borg Høiby (left) to rehab

‘Even if such a diagnosis will limit my life at times, I am glad that the disease has been discovered so early. My goal is still to work and participate in the official programme as much as possible,’ the mother-of-three said. 

Before the announcement of her most recent sick leave, Mette-Marit was last seen alongside King Frederik and Queen Mary of Denmark for the 25th anniversary of the Nordic embassy on October 22.

She was next spotted hosting a lunch for state administrators on November 7 in place of her husband Prince Haakon who cancelled the engagement reportedly to take his stepson to rehab

The Palace communications manager Guri Varple cited ‘private reasons’ for Haakon’s absence however, Se og Hor reported a sighting of the royal boarding a flight from Gardermoen to London at 1pm with Marius, Mette-Marit’s son from a previous relationship. 

In a scandal that rocked the country, he allegedly attacked his ‘girlfriend’ Rebecca Helberg Arntsen, citing his mental health diagnosis as a factor. 

Back in August, Marius, who has no royal title nor official duties, faced preliminary charges of bodily harm and criminal damage after officers responded to a disturbance in downtown Oslo. 

He admitted to and apologised for assaulting Rebecca, thought to be his girlfriend at the time, in a booze and drug-fuelled attack.

In a statement issued via his own lawyer, Marius said he suffers from ‘several mental disorders’ and has ‘struggled with substance abuse for a long time’, which he said he is resuming treatment for. 

In a scandal that rocked the country, Marius, Mette-Marit's on from a previous relationship, allegedly attacked his 'girlfriend' Rebecca Helberg Arntsen, citing his mental health as a factor

In a scandal that rocked the country, Marius, Mette-Marit’s on from a previous relationship, allegedly attacked his ‘girlfriend’ Rebecca Helberg Arntsen, citing his mental health as a factor

The scandal came just days before the controversial wedding of Princess Märtha Louise's and Shaman Durek Verrett which Marius did not attend

The scandal came just days before the controversial wedding of Princess Märtha Louise’s and Shaman Durek Verrett which Marius did not attend

Norwegian media reported the Prince and Princess were made aware ahead of time that Marius was going to be arrested on suspicion of assault

Norwegian media reported the Prince and Princess were made aware ahead of time that Marius was going to be arrested on suspicion of assault

Marius was taken into custody and spent the night in a police cell while Ms Helberg Arntsen was treated for her injuries in hospital following the domestic incident, which also resulted in the destruction of the property.

By the time Marius was spotted boarding the plane with his stepfather, he said to have finished being questioned by police regarding the incident.  

The scandal came just days before the controversial wedding of Princess Märtha Louise’s and Shaman Durek Verrett. 

Marius was confirmed to not be attending the nuptials by the palace but no reason was cited. 

Norwegian media reported that the Crown Prince and Princess were made aware ahead of time that Marius was going to be arrested on suspicion of assault, after the police notified the Royal Court of their intention to take him into custody.  

A spokesman for the Royal Court told VG: ‘The police notified the Royal Court and the Royal Court then informed the Crown Prince couple about an incident involving Marius Borg Høiby and about a possible arrest.’

‘As is known, the police also notified Marius Borg Høiby ahead of the arrest. The police chose not to make an arrest at his residence, and have never searched it.’

FEMAIL contacted the Norwegian Palace for more information.