The trading sentiment turned weak in futures trade after oil prices tumbled further in Asia as concerns eased that fresh Western sanctions on Russia over Ukraine would have an immediate impact on global oil supplies, analysts said.
Meanwhile, West Texas Intermediate (WTI) crude oil for September was down 66 cents at USD 99.61 a barrel, while Brent North Sea crude eased 29 cents to USD 106.22 per barrel in mid-morning trade on the New York Mercantile Exchange.