She combined the dress with black and white heels and a small purse of the same colours.
Taking to social media, fans commented on Camilla’s style.
“Both the Duchess of Cambridge and the Duchess of Cornwall look effortlessly lovely!” said one user.
“Beautiful SM the Queen and the Duchess of Cornwall, elegant beautiful as ever,” said another.
She completed the look with a pearl necklace and matching earrings.
Camilla was all smiles while talking to the G7 leaders.
The Duchess of Cornwall’s fashion choice is perfect for a summer evening.
Kate also dressed for the warm weather and chose a summery gown.
She wore a bright white fit and flare coat dress.
The Duchess of Cambridge finished the look with a pair of nude heels.
She was carrying a small clutch bag.