Brent futures were down 59 cents, or 0.5%, at $108.19 a barrel, while U.S. West Texas Intermediate futures were off 57 cents or 0.6%, at $103.68 a barrel at 0906 GMT.
"Asian buyers have been absent today, with volumes potentially being curbed by the long weekend across most of Asia, Europe, and North America," OANDA analyst Jeffrey Halley wrote in a note. At the same time, major global trading houses are also planning to curtail crude and fuel purchases from Russia's state-controlled oil companies in May, Reuters reported on Wednesday.