Oil prices eased on Friday as Russia hinted it may gradually increase output, after having withheld supplies in concert with producer cartel OPEC since 2017.

Brent crude futures LCOc1 were at $78.63 per barrel at 0534 GMT, down 16 cents from their last close, and more than 2.2 percent below the $80.50 multi-year high they reached on May 17. Brent broke through $80 for the first time in more than three years earlier in May, as reported by Reuters.

U.S. West Texas Intermediate (WTI) crude futures were at $70.60 a barrel, down 11 cents from their last settlement.

"Oil prices are now starting to drift a little," said Greg McKenna, chief market strategist at futures brokerage AxiTrader, adding that this was due to OPEC's and Russia's "moves toward an increase in production" at a meeting scheduled for next month.

Read alsoOil prices drop on expectations OPEC could boost output – Reuters

The Middle East dominated Organization of the Petroleum Exporting Countries (OPEC) as well as a group of non-OPEC producers led by Russia started withholding output in 2017 to tighten the market and prop up prices.

But Russia, in particular, has been floating a potential end to the production cuts, with energy minister Alexander Novak saying on Thursday that restrictions on oil production could be eased "softly" if OPEC and non-OPEC countries see the oil market balancing in June.

"The Russians have always struck me as production cut tourists keen to get off the boat and crank up production as soon as inventories were stabilized and prices once again elevated... That possibility is top of the mind for traders and as a result oil prices are slipping," McKenna said.

Still, the downside risk to oil prices could be limited by geopolitical factors.

"Oil prices, however, look primed to withstand the slip as heightened geopolitical risks from the Middle East, (and) raised prospects of a supply squeeze in Venezuela and Iran permeates global market sentiment," Benjamin Lu, an investment analyst at Phillip Futures in Singapore said in a note to clients.