Oil extended declines on Thursday as geopolitical tensions eased slightly and rising numbers of COVID-19 cases in China added to worries over demand in the world's largest crude importer.
Poland and NATO on Wednesday said a missile that crashed inside NATO member Poland was probably a stray fired by Ukraine's air defenses and not a Russian strike, easing fears of the war between Russia and Ukraine spilling across the border.
"It looks like we aren't seeing an immediate escalation from the Russians and that has tentatively removed some of the short-term supply risks," said Edward Moya, senior market analyst at OANDA.
Brent crude was down $1.48, or 1.6%, to $91.38 a barrel by 1310 GMT. U.S. West Texas Intermediate (WTI) crude slid $1.71, or 2%, to $83.88.
Concern about weak demand in China also weighed on the market after the country reported rising daily COVID-19 infections.
Chinese refiners have asked to reduce Saudi crude volume in December, Reuters has reported, and are also slowing Russian crude purchases.
"Struggling Chinese consumption is embodied in sinking domestic need for both Russian and Saudi crude oil," said Tamas Varga of oil broker PVM.
While China's COVID caseload is small compared with the rest of the world, it maintains stringent policies to quash outbreaks before they spread, dampening fuel demand.
Oil gained some support from official figures that U.S. crude stocks fell by a bigger than expected 5 million barrels in the most recent week.
Supply is also tightening in November as OPEC and its allies, known collectively as OPEC+, implement their latest output controls to support the market.