NATO on Friday launched one of its biggest naval deployments since Russia's invasion of Ukraine, with French aircraft carrier the Charles de Gaulle under the command of the alliance for the first time.

The carrier and its accompanying vessels, known as a carrier strike group, are the centrepiece of Neptune Strike, a series of drills that NATO says will help its members learn to work more seamlessly together and deter its enemies.

The French nuclear-powered carrier began its mission in the Mediterranean Sea, close to its home port of Toulon.

Placing the Charles de Gaulle under NATO operational control for the first time is highly symbolic, not least because the warship is named after the former president who took France out of the alliance’s U.S.-led command structure in 1966.

France returned in 2009 but officials say Paris' interest in NATO exercises and missions increased after Russia’s invasion of Ukraine in February 2022, reflecting a view that a more assertive Moscow made NATO more vital to French security interests.

The decision to put the nuclear-powered aircraft carrier under NATO command drew criticism from the French far left and far right, who said it represented a loss of sovereign power.

French officials say the move is a normal part of being a member of a multinational military alliance.

Rear Admiral Jacques Mallard, the strike group’s commander, said it was in keeping with France already having some land and air forces under NATO command to deter Russia in eastern Europe.

"It’s important because it allows us to remain in the chain of command and to know better the people we could be working with in the case of a crisis," Mallard said on board the Charles de Gaulle as it cruised off the southern French coast.

The deployment will involve some 20 vessels, including carrier strike groups from Italy, Spain and Turkey, he said. Its tasks will include long-range flights to simulate strikes in support of troops in eastern Europe.

On the eve of the mission, ambassadors to NATO from its 32 member countries visited the carrier, watching as grey Rafale fighter jets – catapulted by steam – took off from the flight deck under a pale blue sky.

'ENHANCED VIGILANCE'

The North Atlantic Treaty Organization has held various iterations of Neptune Strike – which it calls "enhanced vigilance activity" - over the past two years.

U.S. Vice Admiral Thomas Ishee, commander of NATO’s Striking and Support Forces, said the latest version - which lasts until May 10 - was among the biggest.

He said it would help allies work more smoothly together and "provide a degree of deterrence that our enemies would … see (as showing) that we do have the capability and the capacity and the cohesion to operate as a large force together".

While Neptune Strike is not explicitly billed as a message to Russia, NATO's strategic concept identifies Moscow as the most significant threat to its members' security.

Russian President Vladimir Putin has said he has no plans to attack NATO countries. This has not reassured NATO members, given that he also said he had no plans to invade Ukraine before sending tens of thousands of Russian troops into that country.

"NATO is not at war with Russia, but we are very concerned with Russia and we are very interested in deterring Russia against aggression," said Ishee.

(Reporting by Andrew Gray; Editing by Gareth Jones)