Oil prices rose in Tuesday's trading, after Libya announced the status of "Force Majeure" in the loading of the ports of "Zouitina" and "Al Hariga" yesterday.
Libya's state-run National Oil Corporation (NOC) said it had declared force majeure after the authorities shut down oil ports in the east.
"It could result in losses of 850,000 barrels per day of crude oil and daily revenues of $ 67.4 million," it said.
But gains were offset by an increase in OPEC production of 320,000 barrels per day in June, compared to the previous May production.
Brent crude for September delivery rose 0.48 percent, or 37 cents, to $ 77.67 a barrel.
US crude futures for August delivery rose 0.78 percent, or 58 cents, to 74.52 dollars a barrel.