DUBAI, July 31 (Reuters) - Du DU.DU , the United Arab Emirates' No.2 telecom operator, extended its earnings slump as it reported an 11.3 percent fall in its second-quarter net profit on Sunday.

The firm, which ended rival Etisalat's ETEL.AD domestic monopoly in 2007, had reported declining profits in the preceding six quarters, according to Reuters data.

Du made a net profit of 445.4 million dirhams ($121.3 million) in the three months to June 30, down from 502.0 million dirhams in the year-earlier period.

Analysts at EFG Hermes and SICO Bahrain forecast du would make a quarterly profit of 433.8 million dirhams and 487.1 million dirhams, respectively. urn:newsml:reuters.com:*:nL8N1AE8IG

Second-quarter revenue was 3.07 billion dirhams, mostly steady versus the 3.09 billion dirhams recorded in the corresponding year-ago period. ($1 = 3.6724 UAE dirham)

(Reporting by David French; Editing by Himani Sarkar) ((davidj.french@thomsonreuters.com; +971 4 362 5864; Reuters Messaging: davidj.french.thomsonreuters.com@reuters.net))