Ankara: Turkey said Friday it has received "positive signals" from the United States over its requests to extradite Pennsylvania-based preacher Fethullah Gulen whom Ankara accuses of ordering last month's attempted coup.

"We have started to receive some positive signals on the calls we have made" for Gulen`s extradition, Foreign Minister Mevlut Cavusoglu told reporters in Ankara, saying further documents relating to the case for his deportation were being drawn up to send to Washington.

Gulen is accused of ordering the July 15 coup during which a group within the military tried to remove President Recep Tayyip Erdogan from power. He strongly denies the claim.

Since then, Turkey has sent several documents to the United States which Ankara claims proves that Gulen was involved.

"Everyone in the world knows who is behind this coup attempt," Cavusoglu said. Last week, an arrest warrant was issued in Turkey for Gulen.

The minister said Secretary of State John Kerry and Vice President Joe Biden expressed their intention to come to Turkey but would not confirm previous comments made by Ankara that Kerry would visit on August 24.