U.S. Defense Secretary Mark Esper said on Monday that he needed to speak with his Turkish counterpart to understand how serious President Tayyip Erdogan was when he said he could shut down the Incirlik airbase, which hosts U.S. nuclear warheads.
Erdogan's warning on Sunday that he could close Incirlik came in response to threats of U.S. sanctions and a separate U.S. Senate resolution that recognized mass killings of Armenians a century ago as genocide.