Oil prices had pulled back somewhat by Monday as demonstrators and the international community ramped up pressure on Libyan leader Moammar Gadhafi.
As much as 700,000 barrels of oil reportedly left the Libyan port of Tobruk from rebel-held territory late Sunday, The Wall Street Journal reports.
The shipments from the Tobruk port would be the first to leave Libya since Feb. 19, before the country descended into political chaos.
The China National Petroleum Corp. became the latest major oil company to pull its non-essential staff out of Libya as violent protests continued.
The International Energy Agency said about 1 percent of the global oil supply was cut out of the market because of unrest in Libya.
Gadhafi's control over the country is starting to slip, though revenue from oil exports in rebel territory still go into accounts controlled in Tripoli, the Journal adds.
The IEA and members of the Organization for the Petroleum Exporting Countries said spikes in crude oil prices aren't justified because there are adequate supplies on the market and plenty of reserve capacity on hand.