Oil prices eased a few cents early in trading on Friday in a breather at the end of a week of big gains propelled by a strike in Norway that raised the prospect of supply from the major producer being slashed by up to 25%.
Brent was down by 9 cents at $43.25 a barrel by 0152 GMT, having gained more than 3% on Thursday. U.S. West Texas Intermediate (WTI) crude dropped 5 cents at $41.14 after also falling more than 3% on Thursday, as reported by Reuters.
Both contracts are on track for gains of around 10% this week - the first rise in three weeks - yanked higher by the prospect of tighter supply on production outages in the North Sea because of the action by Norwegian oil workers.
Read alsoFinancial crisis: Ukraine significantly reduces imports, exports of goods"This could see almost one million barrels a day of crude oil impacted," ANZ Research said in a note.
Norwegian oil company and labour officials said they will meet with a state-appointed mediator on Friday in an attempt both sides hope will bring an end to a strike that threatens to strip out about a quarter of the country's oil and gas output.
Elsewhere, market watchers are also bracing for the impact on U.S. production of Hurricane Delta, forecast to strike the Gulf Coast within hours. Nearly 1.5 million barrels of daily output has been halted so far.