CAIRO, Aug 7 (Reuters) - The average yields on Egypt's three- and seven-year treasury bonds fell at an auction on Monday, central bank data showed.

The average yield on the three-year bonds dropped to 16.813 percent from 18.652 percent at the last such auction on July 24. The seven-year bond yield fell to 16.750 percent from 18.596 percent when last sold.

(Reporting by Amina Ismail; Editing by Catherine Evans) ((amina.ismail@thomsonreuters.com; +20 2 2394 8114;))