"Our minister assured the Russian ambassador that there are no talks that Turkey will provide the United States with the opportunity to study the S-400 air defence systems", the source said.
Cavusoglu tweeted Wednesday he had met with Yerkhov, but did not provide details on the agenda.
Recently, Bloomberg citing two sources reported that Turkey had allegedly offered the United States to explore the S-400 air defence system, which Russia is set to deliver in the near future under the contract.
Earlier, Turkish Foreign Minister Mevlut Cavusoglu confirmed that Ankara had already finalized the S-400 deal and will buy the missile systems from Russia "without any question".
Last December, Ankara signed a loan agreement with Moscow envisaging deliveries of the Russian-made S-400 air defence systems to Turkey. Sergey Chemezov, chief executive of Russia's state-owned defence company, Rostec, said some four S-400 battalion-size sets worth $2.5 billion could be supplied, with 55 percent of the contract sum being covered by Russian loans.