Global oil supply increased in July despite sanctions on Russia's oil and gas industry and turmoil in the Middle East, the International Energy Agency said.

Supplies rose by 230,000 barrels per day to 93 million barrels per day, largely a result of higher production from the Organization of Petroleum Exporting Countries as output from outside the oil cartel slipped.

That should help oil prices remain relatively stable for a while as North American energy production keeps churning and OPEC states pump out a 5-month high 30.44 million barrels per day.

"[A] boost from Saudi Arabia to 10 mb/d and a tentative recovery in Libyan output more than made up for declines in Iraq, Iran and Nigeria," the Paris-based agency said in its monthly "Oil Market Report."

Worldwide oil demand growth is expected to slow for the rest of the year, but will accelerate in 2015, the IEA said.