Mumbai, Nov 24 (IANS): The upcoming winter session of parliament and derivatives expiry subdued Indian equity markets during the mid-afternoon trade session on Tuesday.

The barometer 30-scrip sensitive index (Sensex) of the Bombay Stock Exchange (BSE) was trading flat. It was marginally higher by 29 points or 0.11 percent.

Similarly, the wider 50-scrip Nifty of the National Stock Exchange (NSE) was trading flat during the mid-afternoon session. It gained 10 points or 0.12 percent to 7,858.75 points.

The S&P BSE Sensex, which opened at 25,785.61 points, was trading at 25,848.69 points (at 2.00 p.m.), 29.35 points or 0.11 percent from the previous day's close at 25,819.34 points.

The Sensex so far has touched a high of 25,901.56 points and a low of 25,703.86 points during the intra-day trade.

Market observers pointed-out that investors were reluctant to take positions ahead of the upcoming winter session of parliament and derivatives expiry scheduled for later this week.

"Lack of fresh triggers, caution over the upcoming winter session of parliament and consistent selling by the foreign investors subdued markets and capped investor participation," Anand James, co-head, technical research desk with Geojit BNP Paribas Financial Services, told IANS.

Furthermore, investors are concerned over government's ability to pass key economic legislations, especially after Bihar polls outcome, during the winter session that begins on November 26 and will run till December 23.

The government needs to get the Goods and Services Tax (GST) bill passed in the upcoming session to meet the April 1, 2016, roll-out deadline.

"There were concerns over an extended rate hike in the US commencing from December after yesterday's US Federal Reserves unscheduled meet," James said.

The US Fed held an 'unscheduled' meet on Monday. The meet precedes the federal reserve policy meet in December, when a rate hike is expected to be announced.

The US central bank has given signs that it might go in for a series of gradual rate hikes starting from December.

However, in the short term, higher interest rates in the US are expected to lead away FPIs (Foreign Portfolio Investors) from emerging markets such as India. 

Besides a US rate hike, the derivatives expiry slated for Thursday has caused some nervousness, as Securities and Exchange Board of India (SEBI) has reduced the lot size in futures and options (F&O) segment which has resulted in lower volumes.

This has indirectly rubbed on the trading dynamics of the cash segment.