Oil prices fell back slightly on Thursday, a day after settling at multi-month highs on U.S. President Joe Biden's latest sanctions targeting Russia and a larger than forecast fall in U.S. crude stocks.

Oil futures were up strongly Monday, with Brent crude on track for its first finish above $80 a barrel since August, as investors assess the potential hit to supply from a further tightening of U.S. sanctions on Russia’s oil sector.

Brent crude futures were down 37 cents to $81.66 per barrel by 1042 GMT, while U.S. West Texas Intermediate crude futures slid 35 cents to $79.69

The sanctions imposed by the United States on January 10 against the Russian oil sector have halted about one-tenth of Russia's shadow fleet. The value of the oil it transports could exceed $3.5 billion.