SkyTeam is the first such alliance to welcome a Russian carrier.

With the addition, SkyTeam will serve about 373 million passengers with nearly 15,000 daily departures to 728 destinations in 149 countries.

An official welcoming ceremony with key executives from the alliance was held in Moscow.

"SkyTeam's expansion strategy is simple: the alliance is committed to serving the destinations our customers want to travel to most," said Jean-Cyril Spinetta, chairman and chief executive officer of Air France.

"As we welcome Aeroflot into the alliance, our network now includes new markets in Russia and Eastern Europe that are poised for even greater passenger demand.

"With the addition of Sheremetyevo International Airport and particularly the opening of the new Aeroflot terminal 3 next year, SkyTeam offers passengers greater access and connectivity to the world," Spinetta said.

Aeroflot, the largest carrier in Russia and the Commonwealth of Independent States, has made much progress over the past five years, enabling it to meet international standards.

In October it passed the International Air Transport Association Operational Safety Audit, confirming its operational standards. It also last year received an award for Onboard Service Improvement Excellence from Skytrax, a research and consultancy firm for the airline industry.

Membership of SkyTeam will advance Aeroflot's growth and enhance operational efficiencies for customers, said Valery Okulov, its CEO and chairman.

"We look forward to better serving our customers by linking them to the extensive SkyTeam network and providing them with more convenient connections, as well as the opportunity to earn more frequent-flyer miles as they travel throughout the world," he said.

As a member, Aeroflot passengers will be able to accrue and redeem frequent-flyer miles on any of the nine other SkyTeam member airlines.

In turn, SkyTeam passengers on flights operated by Aeroflot can earn miles in its frequent-flyer programme.