Brent crude futures fell 0.5%, to 80.21 USD a barrel by 02:31 GMT, while US West Texas Intermediate crude futures were at 75.18 USD a barrel, down 0.5%.

Both contracts rose slightly last week, their first weekly gain in five, underpinned by expectations that Saudi Arabia and Russia could roll over voluntary supply cuts into early 2024 and OPEC+ might discuss plans to reduce further.

ING analysts said market sentiment remains negative given the dispute within OPEC+ over production quotas, although they expect Saudi Arabia to roll over its additional voluntary cut of 1 million barrels per day into next year.