Mellitah Oil and Gas terminal
A general view taken Jan. 6, 2015, shows the Mellitah Oil and Gas terminal on the outskirts of Zwara in western Libya. Mahmud Turkia/AFP/Getty Images

French Defense Minister Jean-Yves Le Drian said Monday the Islamic State group is eyeing Libyan oil as it spreads from its stronghold in the coastal city of Sirte to deeper within the North African nation. Le Drian’s warning came as world powers try to convince Libya’s rival administrations to form a national unity government to stop ISIS militants from expanding their foothold, according to France24 News.

"They are in Sirte, their territory extends 250 kilometers (155 miles) along the coast, but they are starting to penetrate the interior and to be tempted by access to oil wells and reserves," Le Drian reportedly told RTL radio.

Libya plunged into chaos after the fall of dictator Moammar Gadhafi in 2011.The Islamic State group, also known as ISIS or ISIL, has exploited the power vacuum. The country has had two rival administrations since August 2014, when a well-armed alliance of militias took over the capital Tripoli and forced the government to retreat east.

With around 3,000 fighters currently operating in the country, ISIS has solidified its grip on Libya by seizing the central city of Sirte. Just this year, the Islamic extremists have attacked a hotel and a prison in Tripoli, oil fields and military checkpoints. The group also released a video of its militants beheading 21 members of Egypt’s Coptic Christian minority on a Libyan beach, according to AFP news agency.

Representatives from 17 countries signed a joint statement Sunday calling for Libya’s warring factions to lay down their arms and form a unity government, vowing to cut off contacts with those who do not sign the United Nations brokered agreement. U.S. Secretary of State John Kerry said Libya’s two governments have pledged to sign the deal Wednesday in Morocco to form a unity government within 40 days, according to Reuters.