Singapore -

Oil prices tumbled further in Asia on Thursday as concerns eased that fresh Western sanctions on Russia over Ukraine would have an immediate impact on global oil supplies, analysts said.

The US benchmark, West Texas Intermediate (WTI) for September delivery, slipped 66 cents to $99.61 while Brent crude for September was down 29 cents at $106.22 in mid-morning trade.

WTI fell 70 cents in New York trade and Brent lost $1.21 in London on Wednesday despite upbeat US stockpiles and economic growth data.

“As Russia has yet to respond to the (new) US and European Union sanctions with actions that could impact oil supplies, fears of disruption in crude stocks abated and helped to ease benchmark prices,” said Sanjeev Gupta, head of the Asia-Pacific oil and gas practice at consultancy EY.

Washington and Brussels announced on Tuesday the strongest sanctions against Russia since the Cold War over Moscow's annexation of Crimea and support for Ukraine separatists who are accused of shooting down a Malaysian passenger jet this month.

Rosneft, Russia's state-held oil giant, is one of the targets of the sanctions, with a tightening of western exports of technology needed to explore and extract energy from remote Russian regions.

The firm said last week it is working on plans to minimising the impact of the sanctions.

The oil market mostly shrugged off better-than-expected official US gross domestic product and stockpiles data.

The US economy grew a forecast-beating 4.0 percent in the second quarter, rebounding from a 2.1 percent slump in the first three months linked to severe winter weather, the Commerce Department reported.

The Department of Energy said crude-oil stockpiles fell 3.7 million barrels to 367.4 million in the week ended July 25, more than double what was expected.

Gupta said major declines in oil prices are not expected as “conflicts in Libya, Ukraine, Iraq and Israel continue to pose a risk of disruption in the supply of crude”. - Sapa-AFP