An alleged member of the Fetullah Gulen organization was invited on Wednesday to speak to a congressional panel on Turkey, a stunning move that could exacerbate tensions between Ankara and Washington.
Ahmet Sait Yayla was added to the original list of speakers to address the House Foreign Affairs Subcommittee on Europe, Eurasia and Emerging Threats, just hours before the hearing on the 15 July coup attempt in Turkey.
Yayla, who was chairman of the sociology department at Harran University in Turkey, and a former police chief, escaped to the US in November 2015 after it became public he had alleged links to the organisation's leader, Fetullah Gulen.
Turkey revoked Yayla's passport and accused him of being a member of Gulen's organisation it says carried out the coup attempt. Gulen has denied the accusations.
Analysts believe that allowing an alleged Gulen member to address US lawmakers will, undoubtedly, put further strain on relations between Ankara and Washington surrounding Gulen's extradition.
During his panel presentation Yayla not only defended Gulen as being free from involvement in the coup attempt, but he even claimed the Turkish government and President Recep Tayyip Erdogan plotted the overthrow.
Turkey has officially submitted to the US all evidence that Gulen's network established a quasi-state within the Turkish state in an attempt to topple the government.
The Turkish authorities have meanwhile issued an official request for the extradition of Gulen under a 1979 treaty between Turkey and the US.
Yayla's appearance triggered reaction from Turkish-American organisations in Washington.
The Turkish Heritage Organisation Vice President, Ali Cinar, told Anadolu Agency his organization had been trying for weeks to have one of its experts added to the list of speakers but was denied the request on grounds the panel was limited to just three speakers.
"There was just three speakers on the list until yesterday but we regretfully saw that Yayla was added to the list today," Cinar said. "These kinds of stunning moves do not help to better Turkish-American relations."
He said Turkish organisations would monitor developments surrounding Yayla's testimony.