A new statement came from Russia on the S-400 deal. "I can confirm on behalf of the Kremlin that the S-400 deal is going according to plan," Kremlin spokesman Dmitriy Peskov said Friday.

Speaking about Turkey's purchase of S-400 air defense systems, Peskov said there is no problem with the delivery of S-400s.

"I will not say the date now, but you will see the second week of July comes," Ismail Demir, president of Turkish Presidential Defense Industry, said Thursday on the S-400s delivery timetable.

The US had previously threatened to impose sanctions in response to the purchase of the Russian system while the Pentagon announced last month that it halted training Turkish pilots to fly F-35 warplane.

But after Turkish President Erdoğan had a meeting with the US President Trump at the G20 summits last month, said Turkey will be spared the US sanctions. (ILKHA)