A big oil leak in the Moroccan desert has prompted the government to announce a national alert and is expected to last up to three weeks.
Militants in the eastern Libyan city of Benghazi have been pushing towards the port city of Sirte since Friday.
The U.S. State Department said on Monday that it had sent three teams of divers to the city to search for the oil.
The United Nations is working to determine the extent of the oil spill, which has already forced hundreds of thousands of people from their homes.
More:U.S., European nations, the International Monetary Fund, European Union, U.N. help in Libyan port rescueThe Associated Press contributed to this report.