Brent crude futures gained 1 cent to $78.99 a barrel at 0239 GMT, while U.S. West Texas Intermediate (WTI) crude futures slipped 2 cents to $76.06 a barrel.
The two benchmark contracts both climbed more than 1% on Monday.
The Organization of the Petroleum Exporting Countries (OPEC), Russia and allies - together called OPEC+ - are due to meet on Tuesday. The Joint Ministerial Monitoring Committee is due to meet at 1200 GMT, followed by a ministerial meeting at 1300 GMT, both by videoconference.
Three OPEC+ sources told Reuters the group is likely to stick to its plan to increase output by 400,000 barrels per day in February, as it has done each month since August.
RBC Capital Markets analysts said OPEC+ was unlikely to change course given the current price outlook, pressure from the administration of U.S. President Joe Biden to boost supply, and no major new COVID-19 mobility curbs.
"Though Omicron (COVID-19 variant) cases continue to climb in key geographies, the absence of widespread lockdown restrictions will likely keep near-term demand concerns in check," RBC analysts said in a note.
However they said OPEC+ may have to change tack if tension between the West and Russia over Ukraine flares up and hits fuel supplies, or Iran's nuclear talks with major powers make progress, which would lead to an end to oil sanctions on Iran.
"We think these two events represent major wildcards that could quickly alter the price trajectory and test OPEC's rapid response mechanism," RBC analysts said.
