Mumbai, Mar 15 (IANS): After gaining for two straight sessions, key Indian stock indices were trading flat on Tuesday morning.

Trading at other Asian markets was also cautious ahead of the decisions over next two days by some central banks, notably in Japan and the US.

The sensitive index (Sensex) of BSE, which had closed on Monday at 24,804.28 points, opened on the next day slightly higher at 24,832.04 points. Soon after, it was trading marginally lower at 24,786.03 points, with a small loss of 18.25 points or 0.07 percent.

At the National Stock Exchange (NSE), the broader 50-share Nifty, which had ended at 7,538.75 points, was trading at 7,535.85 points, with a small loss of 2.90 points, or 0.4 percent.

On Monday, while the Sensex had ended higher by 86.29 points, or 0.35 percent, over the previous day's close, the Nifty closed 28.55 points, or 0.38 percent, up.

Keenly watched will be the two-day meeting of the US Federal Reserve's Federal Open Market Committee that begins on Tuesday, and before that, any decision by the Bank of Japan later on Tuesday, analysts said.

"US stocks closed mixed in low-volume trade on Monday, mostly shaking off the decline in oil prices, ahead of the Fed meeting later in the week," Angel Broking said in an analysis before the opening bell for bourses in India.

"Dow Jones hit new highs for 2016 on Monday, while S&P 500 edged lower as losses in materials and energy sector capped gains seen across Consumer-discretionary sector. Key European indices ended Monday's trading session in green," the brokerage added.