"Our meeting with President (Donald) Trump was very positive. They support us on the deals of S-400 and F-35s," Erdogan told Turkish journalists on Sunday after his meeting with his US counterpart Donald Trump in Japan where he participated G20 summit.
"I am of the opinion that we will overcome this process without any problem," Erdogan said, adding that the first delivery of the S-400 missile defence system would take place within 10 days.
The Turkish leader said that Trump agreed with him to delegate officials to follow the issue and "open the doors" to resolve the matter, Xinhua news agency reported.
The US administration has threatened to impose severe sanctions on Turkey if the S-400 missiles deal with Moscow is followed through.
Washington repeatedly warned that it will cut off Turkey's purchase of F-35 fighters if Ankara goes ahead with the delivery of the S-400s.
Erdogan recalled that Ankara wanted to buy US Patriot systems during the term of former US President Barack Obama but Washington declined Ankara's demand at the time.
The Turkish President said that when he reminded his US counterpart about this case, Trump told him that "you are right" on the dispute over the purchase of S-400 systems.
( With inputs from IANS )