A 5 per cent overnight plunge in oil prices brought pressure to bear on the oil and gas (O&G) sector on Thursday, depressing the Straits Times Index (STI) by 26.45 points to 3,118.84. Turnover amounted to a subdued 2.3 billion units worth S$1 billion, the lowest one-day total in about 11 weeks. Excluding warrants, there were 163 rises versus 354 falls.

Wall Street fell for a third consecutive session on Wednesday after the US Department of Energy reported that its commercial inventory increased by 8.2 million barrels over the last week, far exceeding the consensus of 2.5 million.

"The data catalysed a new wave of glut concerns as the higher oil price might spur North American production, especially of shale oil, which may ultimately counterbalance Opec's effort to support oil prices," said CMC Markets in its morning commentary. The US market's fall was led by energy stocks.