The two were vacationing with unlikely friends Princess Beatrice and her boyfriend Dave Clark. Clark and the princess have been dating since 2005.
The two couples were seen eating at Le Club 55 beach club and then boarding the royal's chartered yacht.
Clark met Kutcher when he signed on for a space flight on Virgin Galactic, as Clark works in astronaut relations for the company. Kutcher became the 500th person set for a trip in outer space, alongside other celebrities like Justin Bieber, Brad Pitt and Angelina Jolie.
The foursome has been spotted together on several occasions, including dinner at Turkish restaurant Ozer and a double date restaurant crawl, including restaurant Duck & Waffle.