Some 400 Russian sailors have arrived at the western French port of Saint Nazaire for the start of a training mission to learn how to handle the Mistral-class French-made warship.
Paris has sold two of the massive helicopter carriers to Moscow despite clamour from some of its NATO allies that the deal breaks sanctions recently imposed over the Ukraine crisis.
But France has made clear that the 1.2 billion euro agreement to furnish Russia with four warships in total predates the eruption of tensions and is vital for its economy.
The purchase was finalised at the G8 summit in Deauville three years ago. At the time, some NATO members also expressed concern that the vessels could be used against Georgia.
The first of two Mistrals should be delivered from October while two more will be built in Russia.