© FILE PHOTO Tatyana Makeyeva / Reuters
Despite many attempts by the US to derail Turkey's plan to acquire the S-400 air defense missile systems, the state-of-the-art weapons will be fully active next year.

The contract is being carried out "normally" and according to the initial plan, Dmitry Shugayev, the head of Russia's Federal Service for Military-Technical Cooperation (FSVTS), which is responsible for arms trade, told reporters at an expo in Dubai on Sunday.

"We will finish training the Turkish personnel by the end of this year. The system will be placed on combat duty by spring."

The delivery of the S-400s to Ankara began in July. Turkish officials said that the weapon system will be fully operational next April.

The country chose to stick with the contract despite being under constant pressure from the US to scrap the deal, or at least not to place the S-400s on combat duty - as Washington fears it will undermine the security of NATO.

Turkey flatly refused to bow down to the US demands. "We told them that we didn't buy these systems as a prop," Foreign Minister Mevlut Cavusoglu said earlier.