Press TV, Iran July 14, 2017 Friday Turkey to pay $2.5bn for Russian S-400 missiles: Official Russia's S-400 Triumph medium and long-range surface-to-air missile systems ride through Red Square during the Victory Day military parade in the capital Moscow, May 9, 2017. (Photos by AFP) Turkey has agreed to shell out $2.5 billion in order to purchase Russia's most advanced missile defense system S-400, provided that Moscow agrees to transfer the technology as well, an official says. "For Turkey, the key aspect of any deal is transfer of technology or know-how. The Russian agreement to allow two of the S-400 batteries to be produced in Turkey will serve that aim," the unnamed official told Bloomberg on Thursday. Under the deal, Russia would send two S-400 systems to Turkey within the next year and then help the country to domestically produce two more batteries. If true, the deal would be a slap in the face for NATO. The US-led military alliance has tried to prevent Turkey—as a strategic member— from forging close ties with Russia. However, Turkey's drift towards Russia seems to be a direct result of Turkish President Recep Tayyip Erdogan's growing frustration with the West and in particular with America. Ankara has been upset with Washington's lack of respect for its demands on extraditing key opposition figure Fethullah Gulen, whom Turkey accuses of staging last year's botched coup in the country. The Turkish government says it has "85 boxes of concrete evidence" that prove Gulen was behind the coup attempt on July 15 last year, which killed some 250 people and injured over 2,100. Erdogan has also been disappointed with the US' support for some Kurdish groups in Iraq and Syria, which he deems a threat for his country's national security. The move has also been described by experts as Turkey's response to Washington's decision in 2015 to withdraw its Patriot surface-to-air missile system from Turkey's border with Syria. Before turning to Russia, the Turkish military walked out of a $3.4-billion contract for a similar Chinese system under pressure from the US. Neither the S-400 nor its Chinese equivalent, FD200, are compatible with other NATO military systems, meaning that they are not bound by NATO's instructions that prevent Turkey from placing such weapons on the Armenian border, Aegean coast or Greek border. According to the official, the Turkish S-400s would not be equipped with a friend-or-foe identification system, allowing them to be used against all targets without any restrictions. Designed to detect, track and destroy aircraft, drones or missiles as far as 250 miles away, the missile defense system has only been sold to China and India so far.