BUENOS AIRES - Telecom Argentina SA, one of Argentina's top telephone companies, said net profit rose 21 percent in the first quarter as Internet and mobile phone sales increased.

Net profit rose to a higher-than-expected 329 million pesos ($86.8 million) from 272 million pesos in the same period a year ago, the company said in a statement on Friday.

A Reuters poll of five analysts found a median forecast of 277 million pesos, with estimates ranging from 233 million to 309 million.

Operating profit totaled 625 million pesos, up 17 percent year-on-year.

During the quarter, (mobile phone) clients have significantly increased, reaching 15 million subscribers, the company said, adding that consolidated net revenue rose 14 percent to 2.83 billion pesos.

It said it had won 600,000 new clients since December and 2.4 million since March 2008.

Telecom Argentina is controlled by Telecom Italia (TLIT.MI) and an Argentine investor group run by the Werthein family.

The company is at the center of an investigation by Argentine anti-trust authorities probing a possible telecommunications monopoly in the country because one of Telecom Italia's shareholders, Spain's Telefonica (TEF.MC), runs another local operator, Telefonica de Argentina (TEA2.BA). ($1 = 3.7925 pesos on March 31)

(Reporting by Jorge Otaola and Helen Popper; editing by John Wallace)

Argentina