Key stock indices Sensex and Nifty closed almost flat on the last trading day of 2020 on Thursday as investors tracked news related to COVID-19 vaccines rollout across the globe for further bets.

In choppy trade, the 30-share BSE Sensex inched up by 5.11 points 0.01 per cent to its new closing record of 47,751.33.

After opening higher at 47,753.11, the index hit its all-time high of 47,896.97 during the day and touched a low of 47,602.12.

The broader NSE Nifty crossed the record 14,000 level for the first time, touching an intra-day peak of 14,024.85. The 50-issue index pared gains to close at 13,981.75, down by just 0.20 points.

The indices, however, closed the year 2020 with overall gains of around 15 per cent. Sensex gained 15.7 per cent while Nifty jumped 14.9 per cent in the year.

HDFC was the leading gainer among Sensex stocks on Thursday, rising by 1.65 per cent, followed by Sun Pharma, ICICI Bank, Asian Paints, Titan and Infosys.

TCS was the biggest loser, shedding 1.33 per cent. Ultratech Cement, Bharti Airtel, Kotak Bank and Tech Mahindra were among the other major laggards.