The cost of delivering the S-400 missile defense system to Turkey will exceed $2 billion, an official from Russia's state-run defense company Rostec said Thursday.

"The cost of the S-400 deal with Turkey is worth more than $2 billion," Sergey Chemezov, the CEO of Rostec, was quoted as saying by Russia's official TASS news agency.

Turkey recently agreed to purchase the S-400 system from Moscow. Previously, Russian presidential aide Vladimir Kozhin said Moscow received an "advance payment" from Turkey for the defense system.

Meanwhile, the executive committee of Turkey's Defense Industry Undersecretariat convened on Thursday to discuss the modernization of the Turkish Armed Forces (TSK) and improvements in the defense industry infrastructure.

The committee will also address in detail the deal for the purchase of the S-400 missile system.

Chaired by Prime Minister Binali Yıldırım, the meeting included National Defense Minister Nurettin Canikli and Interior Minister Süleyman Soylu for the first time.

Chief of General Staff Hulusi Akar and Defense Industry Undersecretary Ismail Demir also attended.

In recent years, Turkey has sought to build its domestic defense industry to reduce reliance on foreign suppliers.

The S-400 is Russia's most advanced long-range anti-aircraft missile system and can carry three types of missiles capable of destroying targets, including ballistic and cruise missiles.

It can track and engage up to 300 targets at the same time and has an altitude ceiling of 27 kilometers (17 miles).

Western governments have expressed concern over the deal - which Erdoğan said in July had been signed - as it cannot be integrated into the NATO system.

Turkey originally awarded a $3.4 billion contract for a defense system to China in 2013, but canceled that two years later after pressure from NATO.

Turkey's need for an air missile defense system once again became urgent with the start of the civil war in Syria, a country which has a sizeable ballistic missile stockpile able to strike a large portion of Turkey's territory, in addition to biological and chemical weapons.

Turkish officials are concerned that the missiles could be used by the Assad regime in case of a unilateral military conflict or an international military intervention, while the possibility of the missiles falling into the hands of a terrorist group poses greater danger.

The country had to rely on Patriot batteries provided by its NATO allies Germany, the Netherlands and Spain during the conflict, which were withdrawn in 2015.

Turkey faced similar worries during the Iran-Iraq War and the First and Second Gulf Wars due to the ballistic missiles possessed by those countries.

In recent years, Turkey has sought to build its domestic defense industry to reduce reliance on foreign suppliers.