Reportedly, Erdogan will visit Japan on June 28-29, 2019 within the G20 summit.
The purchase of the S-400 air defense system, as well as regional issues will be mainly discussed during the meeting.
Earlier, Turkish Foreign Minister Mevlut Cavusoglu said that specialists from the US and NATO could visit Turkey to make sure that Russian S-400 air defense systems do not pose a threat to NATO.
"Although the US urges Turkey to abandon the purchase of Russian S-400 air defense missile systems, it does not guarantee that it will sell us Patriot air defense systems," Cavusoglu said.
Meanwhile, US Secretary of State Michael Pompeo stated that the US believes that Turkey would not be able to have both US F-35 fighter-bombers and Russian S-400 anti-aircraft missile systems at the same time, as this is technically impossible.
Turkish President Recep Tayyip Erdogan said that Turkey may receive the S-400 missile systems earlier than scheduled.
“Turkey expects to receive the first supplies of S-400 missile systems in July 2019,” the president added.
He stressed that despite appeals from the US, Turkey will not abandon the purchase of the S-400.
Initial reports of negotiations between Russia and Turkey on the supply of S-400 appeared in November 2016.
The signing of a contract was confirmed by the Russian side on September 12, 2017.