With an eye on Libya’s oil fields, Islamic State of Iraq and Levant (ISIL) is fighting to expand its territory beyond its coastal stronghold in Sirte.

French Defense Minister Jean Yves Le Drian said ISIL jihadists have begun to move inland.

“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 told France’s RTL radio.

Libya has the world’s ninth largest (and Africa’s largest) crude oil reserves with 48 billion barrels of proven reserves.

Recent reports said ISIL fighters had launched attacks in the town of Ajdabiyah, east of Sirte. Another report detailed a failed attack in October by ISIL at the Es Sidr oil terminal.

Meanwhile, Libya’s rival governments are expected to sign a UN-backed agreement on Dec. 16 to form a unity government.

Libya descended into chaos after the fall of Col. Moammar Gadhafi in 2011.