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 sanctions on Russia’s oil sector.

Oil prices climbed about 2% to a four-month high on Monday on expectations that wider U.S. sanctions on Russian oil would force buyers in India and China to seek other suppliers.

Goldman Sachs is warning of potential upside risks to oil prices following U.S. sanctions on Russia's energy sector, with Brent crude already approaching $80 per barrel and the possibility of hitting $90 under certain scenarios.

Crude oil prices surge as U.S. sanctions on Russian oil disrupt global supplies, driving Brent crude above $81/bbl to the highest in nearly five months.

Oil prices slipped on Tuesday from the previous day's four-month highs but the market remained supported by continuing focus on the impact of new U.S. sanctions on Russian oil exports to key buyers India and China.

The outgoing Biden administration fired a parting salvo of enhanced sanctions at Russia last Friday, January 10. In so doing, it surprised the oil market and shifted the prevailing bearish market zeitgeist.