Mumbai: India's benchmark stock index fell, led by telecommunications companies as investors sold after recent gains.

Reliance Communications Ltd, the nation's second-largest mobile-phone operator, dropped 3.5 per cent, its biggest loss in more than two weeks. The stock surged more than 10 per cent on December 24 amid speculation Reliance Industries Ltd will buy a stake. Bharti Airtel Ltd, the largest mobile-phone operator, slid 1.9 per cent after gaining 4.7 per cent in the last three trading sessions.

"Investors took money off the table following recent gains in some stocks, especially in the telecom sector," said Ambareesh Baliga, a Mumbai-based vice president at Karvy Stock Broking Ltd. "The markets overall seem lacklustre as there are no fresh triggers for investors to act on."

The Bombay Stock Exchange's key Sensitive Index, or Sensex, lost 44.73, or 0.2 per cent, to 20,028.93 at close in Mumbai. Companies on the measure are valued at an average 19 times estimated earnings, compared with a recent peak of 20.1 times on Nov. 5. The gauge rose 1.1 per cent last week.

The S&P CNX Nifty Index on the National Stock Exchange slid 0.2 per cent to 5,998.10, while the BSE 200 Index retreated 0.3 per cent to 2,476.12.

Reliance Communications fell the most since December 9 to Rs137. Bharti Airtel slid the most in a week to Rs341.90.

Sterlite Industries (India) Ltd., the biggest copper producer, snapped a four-day winning streak, losing 3.1 per cent to Rs179.30.