According to him, Turkey's position on the S-400 "has always been extremely open."
“What we say to the public about the S-400 is really what we think.
The details we voiced on the topic in contacts with our interlocutors - whether they are Western countries or Russia - remain in force, "said Erdogan's adviser.
He added that military-technical cooperation with Russia meets the needs of Turkey and "will continue in the same way as military-technical cooperation with Western countries."
Earlier, Turkish President Recep Tayyip Erdogan, during a meeting with President of the United States Joe Biden on the sidelines of the NATO summit, announced the invariability of Turkey's position on the C-400.