MOSCOW, October 13. /TASS/. Russia will sign an agreement with India on October 15 on the delivery of S-400 Triumf antiaircraft missile systems, Russian presidential aide Yuri Ushakov said on Thursday.

"Following the results of the negotiations between our president and [Indian Prime Minister Narendra] Modi, an agreement will be signed on the delivery of S-400 Triumf antiaircraft missile systems to India, as well as some other documents," he said.

"Part of the documents will be signed behind closed doors," he said.

The Kremlin aide declined to comment on the details of the deal, suggesting that first the document should be signed.

S-400 Triumf

The S-400 Triumf is the most advanced long-range antiaircraft missile system that went into service in 2007. It is capable of destroying aircraft and cruise missiles at a distance of up to 400 km and ballistic targets flying at a speed of 4.8 km per second - at a distance of 60 km.

China has been the first foreign buyer of the S-400 system. The sides announced about signing the contract in the spring of 2015. According to media reports, the deal was worth about $3 billion.

Frigates for the Indian Navy

Russia also plans to sign an agreement on building Project 11356 frigates for the Indian Navy and setting up a Russian-Indian joint venture to produce Kamov Ka-226T helicopters.