Crude prices continued the downward trend Tuesday as investors are less concerned that crude production in Iraq would be disrupted.
Brent crude dropped the most in more than two months and returned to the level before Islamist militants seized the northern Iraqi city of Mosul on June 10.
The violence in Iraq hasn't spread to the south, the source of most of the country's oil output, and dragged down crude prices. Iraq is the second-largest producer of the Organization of Petroleum Exporting Countries (OPEC).
What's more, an official from Libya's oil ministry said Monday that the country's largest and third-largest ports, Es Sider and Ras Lanuf, have 7.5 million barrels of oil ready for export, which also put pressure on oil prices.
Libyan production has been severely disrupted for a year as the rebels have blocked several oil ports. The two ports mentioned above were reopened last Wednesday for crude ship.
Light, sweet crude for August delivery slipped 13 cents to settle at 103.40 U.S. dollars a barrel on the New York Mercantile Exchange, while Brent crude for August delivery slumped 1.30 dollars to close at 108.94 dollars a barrel.