Brent crude gained 16 US cents or 0.2 per cent at US$81.91 a barrel at 4.06 am GMT, while US West Texas Intermediate crude was up US$0.15 or 0.2 per cent at US$79.05 a barrel
Brent crude futures were up 65 cents, or 0.81 per cent, to $80.32 a barrel by 1317 GMT
More than 1,300 flights were cancelled by US airlines on Sunday as Covid-19 reduced the number of available crews
Futures in New York traded above $73 a barrel, though liquidity is dwindling heading into the holiday period
Brent and WTI are both headed for a 1.4 per cent loss this week
Prices had been pressured most of the day due to ongoing concerns that supply growth will outpace demand next year
Brent crude oil futures dropped 98 centsby 14.05 GMT
On Thursday, ratings agency Fitch downgraded property developers China Evergrande Group and Kaisa Group to "restricted default" status
Brent crude futures settled at $75.82, up 38 cents, or 0.5%. U.S. West Texas Intermediate crude ended at $72.36 a barrel, up 31 cents or 0.4%
The move signals that the world's biggest crude exporter still sees strong demand in its two main markets
Lower oil prices can improve margins, but they could impact inventory value while a third Covid wave can potentially hurt growth
The Organization of the Petroleum Exporting Countries and its allies, together known as OPEC+, decided on Thursday to release more oil into the market in January in line with previous months
Gehlot said inflation has shaken people across the country and there is a need to curb it
Oil fell with global equities markets on fears the variant could dampen economic growth
On Wednesday, China said it was working on its own reserves release
Oil prices were largely steady as investors questioned the effectiveness of a U.S.-led release of oil from strategic reserves
Brent crude was up 28 cents or 0.3% at $81.52 a barrel by 0145 GMT, after falling to a six-week low on Thursday before rebounding to close 1.2% higher.
The prospects of speedier interest rate hikes from the Federal Reserve and ongoing supply chain disruptions weighed on Wall Street, while oil dropped on concerns of oversupply and dwindling
Brent crude futures dropped 32 cents, or 0.4%, by 1410 GMT to $82.11 a barrel
The fall came after UN climate talks ended Saturday with a deal that for the first time targeted fossil fuels