WASHINGTON (AP) - U.S. Secretary of State John Kerry says the United States would entertain an extradition request for exiled cleric Fethullah Gulen, whom Turkey's president blames for a failed coup.

But Kerry adds Turkey's government would have to present evidence of Gulen's wrongdoing that withstands scrutiny.

While visiting Luxembourg, Kerry says Turkey hasn't made a request to send the Saylorsburg-based Gulen home. But he says he anticipates questions about Gulen, who has condemned the coup.

Kerry says on Saturday the U.S. opposed any attempt to overthrow a democratically elected leader. He says change must come through a constitutional process.

Kerry also says U.S. military cooperation with its NATO ally has been unaffected by the turmoil.

Turkey plays a key role in U.S.-led efforts against the Islamic State group in Syria and Iraq.