SINGAPORE - Oil was mixed in Asian trade Thursday following an unexpected gain in US crude inventories, analysts said.
New York's main contract, light sweet crude for delivery in February, was up 33 cents at $99.69 (S$129.59) a barrel.
Brent North Sea crude for February delivery was down three cents to $107.53 (S$139.78).
Crude prices were tempered by a weekly forecast by the American Petroleum Institute (API) Wednesday showing a spike in US stockpiles instead of an expected drawdown, analysts said.
API statistics showed a 9.6 million barrel gain in US stockpiles last week while analysts had predicted a 1.9-2.3 million barrel fall.
The US is the world's largest oil consumer and a gain in its inventories would imply a slowdown in its energy consumption, which would drive prices lower.
Financial analysis website fxempire.com said oil prices would be "influenced by (US) dollar strength or weakness going forward, as well as the drama unfolding in the Middle East."
The row between Iran and the US continued Thursday as Washington warned Tehran not to close the Strait of Hormuz - the world's most important oil transit channel - after Tehran's Iran's navy chief said it would be "really easy" to do so.
The strait is a strategic choke point linking the Gulf's petroleum-exporting states of Bahrain, Iran, Kuwait, Qatar, Saudi Arabia and the United Arab Emirates to the Indian Ocean.
Fxempire.com also cautioned that the market would be volatile in the final days of 2011 as trading volume was light.
"The volume is almost non-existent this time of year, making the moves a bit exaggerated," it stated.