ATHENS- Greece sold 812.5 million euros ($959.64 million) of three-month treasury bills to refinance a maturing issue with the yield turning negative, the country's debt agency PDMA said on Wednesday.

The debt agency sold the new paper at a yield of -0.04%, down from 0.01% in a previous sale in July. The amount raised included 187.5 million euros in non-competitive bids.

The sale's bid-to-cover ratio was 2.22, down from 3.03 in the previous auction. Settlement date is on August 7.

($1 = 0.8467 euros)

(Reporting by George Georgiopoulos) ((george.georgiopoulos@thomsonreuters.com; +30210 337 6437; Reuters Messaging: george.georgiopoulos.thomsonreuters.com@reuters.net))