* Net profit at 3.03 bln rupees vs 1.29 bln rupees estimate
* Revenue rises 12 pct, beating estimates
* Reliance Communications weighed down by $7.2 bln debt (Adds details, company comment, background)
NEW DELHI, May 10 (Reuters) - India's Reliance Communications Ltd reported a smaller than expected 8.7 percent fall in quarterly profit as one-off gains helped to offset the impact of a heavy debt load at the country's third-biggest mobile carrier by customers.
Reliance Communications, with net debt of $7.2 billion as of end-March, or more than five times its annual operating profit, is the most-leveraged among listed Indian carriers.
The company has so far been unsuccessful in its efforts to cut debt through stake sales in units, but earlier on Friday said it repaid a $500 million loan it had taken in 2007.
A planned sale of its telecommunications infrastructure unit that had been expected to raise about $3 billion has dragged on for more than two years. Last year, it was forced to shelve a Singapore listing of its undersea cable unit due to weak investor demand.
Reliance Communications, controlled by billionaire Anil Ambani, is in talks with a consortium of private equity firms to sell a stake in a unit that includes the undersea cable assets after talks with Bahrain's Batelco fell through.
Bigger carriers in India, the world's second-biggest market by mobile phone customers, are seeing an uptick in margins and other operating metrics, as easing competition enables them to raise voice call prices. Several smaller carriers either shut down or scaled back operations after a court order.
Reliance Communications recently raised some call prices by about a fifth and reduced discounts, following similar moves by rivals Bharti Airtel Ltd, Vodafone India and Idea Cellular.
"It has started contributing to our financials," Gurdeep Singh, the company's chief executive for wireless business, said in a phone interview, adding the full impact would be visible by the quarter ending in September.
The company is also betting on more network-sharing deals with Reliance Industries, controlled by Anil Ambani's older brother, Mukesh, India's richest man, which is readying a nationwide 4G network, after a pact to lease out its inter-city fibre optics network.
Reliance Communications said consolidated net profit fell to 3.03 billion rupees ($56 million) for its fiscal fourth quarter to end-March, from 3.32 billion rupees reported a year earlier.
That was the third straight quarter of declining profits at the firm, with profits falling in 13 of the last 15 quarters.
Revenue, however, rose 12 percent to 59.56 billion rupees.
Analysts had expected a net profit of 1.29 billion rupees on revenue of 53.47 billion, according to Thomson Reuters I/B/E/S.
Reliance Communications' other income, which includes one-off gains, jumped 175 percent from a year earlier to 8.3 billion rupees, mainly due to a reversal in a provision made previously.
The company saw its average revenue per user rising 7.5 percent from the previous quarter, partly the result of an earlier push to shut inactive subscriber accounts.
Reliance Communications shares, valued in total at more than $4 billion, have more than doubled since the beginning of April on investor hopes of more deals with Reliance Industries.
The fibre optic deal was the first business tie-up between the two brothers since they ended a feud three years ago.
($1 = 54.2300 Indian rupees) (Reporting by Devidutta Tripathy; Editing by Jeremy Laurence and Mark Potter)