The Australian-born royal – who is married to the Crown Prince of Denmark – Prince Frederik – wowed in a scarlet ensemble as she met the French President’s wife, Brigitte Macron.
The pair matched with their vibrant red dresses as they visited the Royal Danish Academy of Fine Arts in Copenhagen.
While Princess Mary wore a calf-length, belted gown which she accessorised with a maroon clutch bag, Brigitte also opted for a high-necked frock, but hers was simpler in design and enhanced with a double-breasted red coat.
Fashion-conscious Princess Mary wore her brunette hair back in a simple chignon – accessorising with a gold broach and earrings, while the President’s wife appeared to go jewellery-free.
Later in the day, both women dressed in their finery as they attended a state dinner with their respective husbands.
The dinner – at Christiansborg Palace in Copenhagen – was also attended by Danish Queen Margrethe.
For the formal occasion, Mary opted for a striking black and white gown, which appeared to have a black train.
She wore a tiara on her head and a blue sash – which is traditional on such occasions.
Prince Frederik, meanwhile, looked handsome in his military regalia.