Global oil prices were under pressure again Thursday after a report from the International Energy Agency said compliance from OPEC members on its agreed production cuts fell to the lowest level of the year last month.

In its regular monthly report, the Paris-based group said cartel members' compliance with its pact to trim production by 1.2 million barrels per day -- which was extended through the end of March 2018 -- slipped to 78% in June from 95% in May. Global oil supply, the IEA said, rose to 720,000 barrels per day last month as major producers such as Saudi Arabia, Libya and Nigeria lifted output.

"Each month something seems to come along to raise doubts about the pace of the rebalancing process," the IEA said. "This month, there are two hitches: a dramatic recovery in oil production from Libya and Nigeria and a lower rate of compliance by OPEC with its own output agreement."

West Texas Intermediate crude futures for August delivery were marked 1% lower from their Wednesday close at $44.99 per barrel following the IEA report, while Brent contracts for September, the global benchmark were seen 1.05% lower at $47.18 per barrel.

The IEA report followed the publication of OPEC's regular monthly oil report, which lowered its forecast for worldwide demand for supply from its members next year to around 32.2 million barrels per day.

The estimate offset solid import data from China, the world's biggest energy consumer, which showed crude imports for the month of June rose 19% from last year to 8.79 million barrels per day.