Mumbai, Dec. 18 -- The headline equity indices ended a volatile session near the flatline with minor cuts, extending losses for the fourth day in a row. Investor sentiment remained cautious amid ongoing uncertainty over a potential U.S.-India trade agreement, which weighed on risk appetite. The Nifty settled below the 25,850 mark.

Media, auto and oil & gas shares declined, while IT, consumer durables and realty shares advanced.

As per provisional closing data, the barometer index, the S&P BSE Sensex shed 77.84 points or 0.09% to 84,481.81. The Nifty 50 index slipped 3 points or 0.01% to 25,815.55. In four consecutive trading sessions, the Sensex slipped 0.92% while the Nifty declined 0.89%.

In the broader market, the S&P BSE Mid-Cap in...