LONDON: Global oil prices tanked Wednesday to a 6.5-year low as a surprise jump in US crude inventories signalled weak demand in the world`s top economy.

US benchmark West Texas Intermediate for September delivery dived to $40.60 per barrel a level last seen on March 2009.

The contract, which has lost more than 30 percent of its value in the past two months, later stood at $40.81, down $1.81 from Tuesday`s close.

Brent North Sea crude for October tum-bled to $46.81 nearing the lowest level since mid-January.

It later stood at $47.24 in afternoon London deals, down $1.58.

The market was pummelled after the US government`s Department of Energy reported that American crude inventories rose by 2.6 million barrels in the weel< to August 14.

Analysts said prices were unlikely to stage a sustained rally because the market remains awash with supplies from the Opec, led by Saudi Arabia.-AFP