Mumbai: The Sensex erased early gains and closed 36 points lower, logging its fourth straight loss, as earnings from Bharti Airtel and ICICI Bank failed to enthuse investors, amid caution ahead of the U.S. Federal Reserve's possible decision to further trim stimulus.

Selling that picked up the last hour of trade in select metal, realty and banking shares before expiry of monthly equity derivatives, also dampened trading sentiments.

After a better start, the Sensex rose over 140 points to 20,828.68 helped by firm Asian cues. However, sustained offloading of stocks led to the 30-share Sensex closing lower by 36.21 points, or 0.18percent, to 20,647.30.

The gauge has now lost over 726 points in four days.

"ICICI Bank reported rise in consolidated net profits in Q3FY14 on a YoY basis, while asset quality was marginally lower. Bharti Airtel too was down post results. Though the results were good but fell short of general expectations," said Rakesh Goyal, Senior Vice President, Bonanza Portfolio

Losses in ICICI Bank, RIL, ITC dragged the index down. The biggest laggards of the day included Tata Steel, Sesa Sterlite, Hindalco and Bharti Airtel.

Maruti shares with a 7percent spurt led the 14 Sensex gainers which included Infosys, Bhel and Hero MotoCorp.

"Although market started on a buoyant note, it succumbed to selling pressure in last one hour of the trading session. The US Fed meeting result will be available tonight. The street is factoring in USD 10 billion tapering," said Milan Bavishi, Head Research, Inventure Growth and Securities.

The 50-share National Stock Exchange index Nifty declined by 6 points, or 0.10percent, to end at 6,120.25, after touching an intra-day high of 6,170.45.

Sectorally, the BSE Metal index suffered the most by losing 1.35%, followed by Consumer Durable index (0.76percent), Banking index (0.69percent) and Realty index (0.58percent).

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