MOSCOW, March 11. /TASS/. China has paid Russia an advance under a contract signed last year for the delivery of S-400 Triumf antiaircraft missile systems, Russia’s state hi-tech corporation Rostec Head Sergei Chemezov told TASS on Friday.

"We still have to go through a whole number of formal procedures, which we have not yet completed, although we have already received an advance payment. I believe we’ll settle these procedures by the end of the year," Chemezov said.

The deliveries of S-400 air defense systems to China under this contract may begin in the first quarter of 2017, Chemezov said.

A source in the system of Russia’s military and technical cooperation earlier told TASS that Beijing would receive the first S-400 antiaircraft missile systems no sooner than in twelve or eighteen months.

China’s deal to purchase S-400 Triumf systems was officially announced in the spring of 2015. Russia’s state arms seller Rosoboronexport Head Anatoly Isaikin didn’t disclose at the time the details of the contract, the number of S-400 systems that would be purchased by China or the timeframe of the deliveries.

According to media reports, the deal involves no less than six S-400 battalions worth a total of $3 billion.

The S-400 Triumf is the most advanced Russian medium- and long-range antiaircraft missile system that went into service in 2007.

As many as 16 regiments of the Russian Army are expected to be armed with S-400 systems by the end of 2016.

China has become the first foreign customer of S-400 antiaircraft missile systems.

One S-400 system can acquire 36 targets at a time with 72 missiles at a distance of 400 km. The S-400 Triumf antiaircraft complex is capable of hitting targets at an altitude of 30 km and can be used against ground objectives.