"The cabinet has signed the decree," the official told AFP, without specifying when the authorisation was given. "The (Incirlik) air base can be used (by the US against IS) anytime."
The accord came after months of tough negotiations between the two NATO allies that saw Washington grow increasingly frustrated over Turkey's reluctance to play a robust role in the international coalition against jihadists.
The decree signed by the cabinet authorises the implementation of an agreement between Turkey and the United States on the base that was thrashed out during a visit to Ankara by US presidential envoy John Allen earlier this month.
The United States has long pushed for the use of the base in the campaign against IS jihadists in Syria due its location relatively close to Syria just outside the Turkish city of Adana.
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