The Kremlin on Wednesday defended Turkey's purchase of the S-400 missile defense system amid NATO concerns over the deal.
"No one has the right to criticize Russia and Turkey for military-technical cooperation, which is carried out in strict accordance with international law and is not directed against any third countries," spokesman Dmitry Peskov said, according to the official TASS news agency.
He added: "Therefore, no one has any reason to express any critical considerations in this regard."
On Monday, Defense Undersecretary Ismail Demir said delivery of the missile system would begin within two years.
The deal has caused concern among Turkey's NATO allies, who say the Russian air defense system is incompatible with NATO systems.
Commenting on Russian President Vladimir Putin's one-day visit to Ankara slated for Thursday, Peskov said the trip had "extremely pragmatic" goals. Putin and Erdogan are expected to cover ties between the countries and the conflict in Syria.
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).
