Oil prices settled slightly lower on Monday, as demand headwinds counterbalanced a widely expected extension of voluntary output cuts through the middle of the year by the OPEC+ producer group.

Brent futures settled down 75 cents to $82.80 a barrel, while U.S. West Texas Intermediate (WTI) settled down $1.24, or 1.5%, to $78.74 a barrel.

The Organization of the Petroleum Exporting Countries and its allies (OPEC+) are extending their voluntary oil output cuts of 2.2 million barrels per day (bpd) into the second quarter to support prices amid global growth concerns and rising output outside the group.

However, the end of a warm winter across the northern hemisphere is weighing on oil prices despite the OPEC+ announcement, said John Kilduff, partner at Again Capital LLC in New York.

"We would have needed sustained heating oil demand to keep the complex up," Kilduff said.

U.S. product supplies of distillate fuel oil, which includes heating oil, declined in December to 3.61 million barrels per day (bpd), down about 10% from November and the lowest since June 2020, data from the Energy Information Administration showed last week.