Oil production is due to resume Wednesday at two oilfields in southwestern Libya, where activities were halted last week when gunmen attacked the facilities, an official said.
Mohamed Hrari, spokesman for Libya's National Oil Corporation, said that "production will resume on Wednesday in the Al-Sharara and Al-Fil fields."
Speaking to AFP on Monday, Hrari said that an attack by gunmen last week had stopped production at the two sites.
Workers at the Al-Sharara oilfield said gunmen launched the attack "motivated by political considerations", forcing guards to withdraw from the site and from the adjoining Al-Fil field.
Al-Sharara, one of Libya's biggest oilfields, can produce up to 350,000 barrels per day, while Al-Fil has a capacity of around 200,000 bpd.
Three years after dictator Moamer Kadhafi was toppled and killed in a NATO-backed revolt, Libya is awash with weapons and powerful militias, and run by two rival governments and parliaments.
Islamist militants overran the capital Tripoli in August after fierce fighting with nationalist forces, and are also in control of most of second city Benghazi.
Libya's economy took a heavy hit when rebels blockaded export terminals in July 2013, causing output to plunge, along with all-important oil revenues.
The seizure of four terminals in pursuit of a campaign for restored autonomy for the eastern Cyrenaica region slashed output to just 200,000 bpd from 1.5 million bpd.
Under a deal with the government, the rebels returned control of two terminals in April and the remaining two in July.
Hrari also said on Monday that exports from the eastern Al-Hariga oil terminal have been suspended since Saturday due to a strike by workers over delayed salaries.
He blamed the delay on fighting in the eastern city of Benghazi.