(Corrects to show cabinet approves agreement, not signs new deal)

ANKARA, July 29 (Reuters) - The Turkish cabinet has formally approved an understanding with the United States which includes opening its air bases to the U.S.-led coalition against Islamic State militants, the Turkish foreign ministry said on Wednesday.

The understanding only concerns the fight against Islamic State and does not include air support to Kurdish fighters in northern Syria, spokesman Tanju Bilgic told reporters in a briefing.

(Reporting by Tulay Karadeniz; Writing by Ece Toksabay; Editing by Nick Tattersall and John Stonestreet) ((ece.toksabay@thomsonreuters.com; +90 212 3507052; Reuters Messaging: ece.toksabay.reuters.com@reuters.net))