Sensex fell on Tuesday in line with Asia and were headed for a sixth straight session of declines, as continued tensions on the Korean Peninsula prompted investors to move into safer assets.
North Korea's foreign minister said on Monday that the United States had declared war on the country and Pyongyang reserved the right to take countermeasures.
Asian shares withered, with MSCI's broadest index of Asia-Pacific shares outside Japan shedding as much as 0.7 percent to a near three-week low.
"Generally, there's a little bit of spookiness which has come about because of geopolitical events surrounding North Korea," said Nitasha Shankar, senior vice president and head of research, YES Securities.
Investors await U.S. Federal Reserve Chair Janet Yellen's speech later in the day for clarity on whether the Fed will stick to its plan to raise interest rates in December.
The broader Nifty was down 0.26 per cent or 26.45 points at 9,846.15 as of 12:45 pm, heading for a sixth straight session of losses after hitting a record high last week.
The benchmark BSE index, Sensex was 0.28 percent lower at 31,536.41.
Financials continued to weigh on the markets, with the Nifty Financial Services index down 0.56 percent.
Oil refiner Bharat Petroleum Corp Ltd fell 4.2 percent and consumer goods company Hindustan Unilever Ltd declined 3.2 percent, putting them among the top percentage losers on the NSE index.