DUBAI - Saudi Arabia's Etihad Etisalat (Mobily) reported a third-quarter loss on Monday, blaming a rule introduced last year requiring fingerprints be registered with SIM cards for shrinking the telecom market.

Net losses at the country's second-largest telecommunications operator widened by 5 percent to 174.5 million riyals ($46.53 million), it said in a statement to the Saudi bourse. Revenue fell 4.3 percent to 2.8 billion riyals.

The result was better than the loss of 188.75 million riyals forecast by four analysts polled by Reuters.

It said the SIM card registration policy had led to an "erosion" of its customer base.

Under Communications and Information Technology Commission rules announced last year, all SIM cards issued in Saudi Arabia must be linked to a fingerprint record held at the National Information Center, part of the Ministry of Interior.

Mobily, an affiliate of the United Arab Emirates' Etisalat, competes with Saudi Telecom (STC) and Zain Saudi.

($1 = 3.7502 riyals)

(Reporting by Alexander Cornwell; editing by Jason Neely) ((Alexander.Cornwell@thomsonreuters.com;))