SINGAPORE  - Bahrain's state oil company BAPCO offered prompt-loading crude in January via a tender in an unusual move, trade sources said on Thursday.

* The producer offered 500,000 barrels of Banoco Arab Medium crude to load during January even though the market is currently trading February-loading cargoes, they said.

* The tender will close on Friday with bids valid until Dec. 19.

* BAPCO could not be immediately reached for comment.

(Reporting by Florence Tan; Editing by Sherry Jacob-Phillips) ((Florence.Tan@thomsonreuters.com; +65 6870 3497; Reuters Messaging: florence.tan.thomsonreuters.com@reuters.net))