Libya's Sharara field restarted production late Thursday after it was offline for more than a week due an unlawful valve closure, sources said Friday.
A source based in the country said the valve was reopened Thursday afternoon and production resumed in the evening, with the output expected to return to normal levels gradually.
Around 300,000 b/d of production at the Sharara oil field was forced offline as the valve was closed by an unidentified group near Zawiya last Tuesday.
Production at Libya's 300,000 b/d Sharara field had been halted for the second time in a month, resulting in a force majeure on crude loadings from the Zawiya terminal.
Force majeure on Sharara loadings -- which was declared on July 30 -- is also expected to be lifted in the next few hours, according to sources.
Libya is embroiled in a protracted civil war as the Libyan National Army, forces loyal to the UN-backed government, and other militia groups have clashed regularly in the past three months.
Representatives at state-owned National Oil Corporation were unavailable for comment.
Analysts expect more short-term outages amid a deteriorating security environment.
Paul Sheldon, chief geopolitical adviser with S&P Global Platts Analytics said the recent closures "raise red flags" and "logic indicates that another major outage lies on the horizon."