Brent crude on Monday fell back slightly from the two-week high hit at the end of last week, but the price remains supported by supply outages and political tensions.
Brent crude for May delivery fell as much as 45 cents to $107.62 a barrel on ICE Futures Europe, having touched $108.39 on Friday, the highest level since March 17.
A lack of diplomatic progress over Russia's annexation of Crimea means the prospect remains of economic sanctions on major oil-producer Russia.
Ongoing production outages in Libya and Nigeria also provide price support.
In the U.S., crude-oil futures were down 13 cents at $101.67 a barrel on the New York Mercantile Exchange, having hit a three-week high on Friday.
The contract's strength is directly related to eight consecutive weekly drain on stocks at the Cushing storage hub, said David Hufton of brokerage PVM.
However, some market watchers have said the focus on Cushing supplies is misleading, because the oil moving out of Cushing is simply entering storage on the Gulf Coast.
"WTI is being priced at a location which is subject to severe local pressures and may no longer be reflecting the true state of the U.S. domestic oil balance," said Mr. Hufton.
Recently the ICE's gasoil contract for April delivery was down $2.00 at $900.75 a metric ton, while Nymex gasoline for April delivery was down 220 points at $2.9155 a gallon.
