Princess Marie's awkward brush with husband's ex-wife

Princess Marie of Denmark has found herself in a rather awkward tussle with her husband's ex-wife.

Marie was attending the graduation of her stepson, Prince Nikolai, from the prestigious Herlufsholm Boarding School, with her husband Prince Joachim.

They were posing for a photograph when Nikolai's mother, Alexandra, Countess of Frederiksborg, appeared from behind and grabbed her son's arm, inserting herself into the group.

She took up position next to the 18-year-old, as Princess Marie quickly removed her arm from his waist.

Alexandra then put her own arm around Nikolai as the group posed for the cameras, Princess Marie appearing momentarily shocked.

The two women exchange polite smiles but the tension is clear.

Prince Joachim looks awkward as the scene plays out, greeting his ex before removing his sunglasses and appearing to fiddle with them before putting them away in his jacket pocket.

Joachim and Marie married in 2008 but he has remained friendly with Alexandra.

She is frequently asked to events involving the royal family, and has been photographed alongside Marie multiple times.

Most recently, Alexandra was invited to Prince Frederik's 50^th birthday celebrations at Christiansborg Palace in Copenhagen.

Last year, Alexandra attended the confirmation of her youngest son, Prince Felix, and posed alongside Princess Marie in the official photos taken inside Fredensborg Palace.

She was also invited on board the royal yacht with the rest of the Danish royals to celebrate Prince Nikolai's 18^th birthday in August.

The dashing prince is currently seventh-in-line to the Danish throne and recently signed a modelling contract, taking part in designer Kim Jones' Dior Homme runway debut.