The S-400 negotiations with Russia continue successfully, yet there is no sign of an agreement, Deputy Prime Minister Numan Kurtulmuş confirmed Monday.

Responding to a reporter's question on the delivery of the first S-400 missiles in 2019, Kurtulmuş said that in order for the mention of a delivery, an agreement needs to be signed first.

"The negotiations continue successfully, yet, they are still not at the point of signing an agreement. After we reach the point of making an agreement, we can talk about the delivery process," Kutulmuş indicated, adding that he hopes for the negotiations to finalize after a positive series of negotiations.

Turkey and Russia have engaged in talks regarding Turkey's cooperation with Russia in the defense sector since the Russian-Turkish rapprochement in August 2016.

The S-400 is a new generation of Russian missile system, which has so far been sold to China and India only.

Last year, both China and India signed an intergovernmental agreement for the procurement of four regiments of Russian-made S-400s. Turkey will become the first NATO-member country to purchase the system.