The Duchess of Edinburgh carried out several engagements in Bosnia and Herzegovina to commemorate the 30th anniversary of the Srebrenica genocide.
Sophie, 60, arrived in Sarajevo on Thursday for the significant diplomatic event.
Her first engagement was a meeting with Željko Komšić, a Croat member of the Presidency of Bosnia and Herzegovina, at the Presidency building in the capital.
The duchess appeared poised during the encounter, which marked the start of her solo trip to the region.
The Duchess of Edinburgh carried out several engagements in Bosnia and Herzegovina to commemorate the 30th anniversary of the Srebrenica genocide.
PA
The visit carries particular significance as it honours the memory of the 1995 genocide, when more than 8,000 Bosnian Muslim men and boys were killed.
For the diplomatic occasion, the duchess selected a designer polka dot dress by Prada.
The 'Georgette' style featured a fitted waistline, straight-point collar and front button detailing, retailing at £3,500.
She paired the sophisticated piece with nude pumps and a coordinating envelope clutch.
The duchess appeared poised during the encounter, which marked the start of her solo trip to the region.
PA
Her blonde hair was styled in an understated low bun, showcasing gold hoop earrings that complemented a matching pendant necklace.
The duchess had previously worn the same Prada dress to King Charles's pre-Christmas lunch at Buckingham Palace in December.
The Bosnia visit follows a series of high-profile appearances by the duchess.
Earlier this week, she attended the State Banquet at Windsor Castle honouring French President Emmanuel Macron and his wife Brigitte.
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The duchess had previously worn the same Prada dress to King Charles's pre-Christmas lunch at Buckingham Palace in December.
PA
For the prestigious event, Sophie wore a white 'Delphine' dress by Suzannah London featuring a tulip-shaped wrap skirt and tailored bodice with puffed sleeves.
She accessorised with the Wessex Aquamarine Necklace Tiara and £24,500 diamond hoop earrings by G.Collins & Sons.
The Duchess also made a stylish appearance at day eight of the Wimbledon Tennis Championships.
She watched from the Royal Box wearing a printed Proenza Schouler dress beneath a crisp white blazer, completing the ensemble with dark sunglasses and a statement gold bangle.