BRUSSELS (Reuters) - The head of NATO said on Thursday that the United States has requested the alliance's help in fighting Islamic State in the Middle East by providing surveillance planes called the Airborne Warning and Control System (AWACS).

NATO is not directly involved in combating Islamic militants in Syria and Iraq, with the United States leading a coalition of nations that includes all 28 NATO allies. NATO member Turkey also shares a long border with Syria and Iraq.

"We have got a request from the U.S. to provide support to the efforts of the coalition, to help them with the NATO AWACS surveillance planes, and we are now looking into that request," Secretary General Jens Stoltenberg told a news conference.

Stoltenberg said NATO defense ministers would discuss the U.S. request at their meeting in early February, although there is no deadline for any decision.

AWACS monitor airspace within a radius of more than 400 km (250 miles) and exchange information via digital data links, with ground-based, sea-based and airborne commanders.

NATO is already sending AWACS to Turkey to strengthen Ankara's air defenses on its border with Syria. It was not immediately clear if those planes will play a dual role.

(Reporting by Robin Emmott; Editing by Hugh Lawson)