Libya's National Oil Corporation (NOC) has told five eastern oil ports to prepare for the lifting of force majeure.
After UN-recognised Government of National Accord (GNA) victories against the rebel Libyan National Army (LNA) in recent weeks, NOC has issued instructions for the export terminals to be ready for a resumption of operations.
The ports - Hariga, Brega, Zueitina, Es Sider and Ras Lanuf - were closed down on the orders of forces linked to the LNA in January.
UN-supervised talks on restarting production are continuing between NOC, the GNA and neighbouring countries backing the blockade.
An unnamed oil tanker is en route to Es Sider port to begin loading crude oil stored in tanks there.
But NOC said force majeure will remain in place until Major General Nagi al-Moghrabi, the Petroleum Facilities Guard commander in the Eastern region, permits the operating companies to resume exports.
Talks limited to oil output
"NOC wants to clarify that the current framework of negotiations is limited to the resumption of production following revenue losses exceeding $6bn as a result of this blockade, in addition to the significant damages to infrastructure and oil reservoirs," it added.
Disruption has led to overall losses in sales opportunities amounting to $231bn since 2011, it said.
"Unfortunately, other oil producing countries have taken advantage of this by compensating Libya's market share. Also, the infrastructure and oil reservoirs were damaged," NOC added
The GNA has recaptured the capital, Tripoli, and may push eastwards to liberate more terminals.
Two major oil fields connected to the western Zawia terminal, Sharara and El Feel, restarted production briefly at the start of June but were then closed again by another militia.
"A small pickup in oil exports out of the west could signal improvements to come, albeit it remains unclear if and when Sharara and El Feel, the country's major onshore fields in the west, might return to full operation," analysts at Kpler said.
"The latest GNA success in the west has seemingly enabled a slight bump in the volume of crude departing the Zawia terminal."
In May, departures out of Zawia averaged 39,000 bpd, the first sign of any positive volumes since February.
This trend of loadings has maintained into June, likely as a result of draws from storage.
Total Libyan departures remain "muted", Kpler said, holding at just 143,000 bpd so far this month, against 1.1m bpd in the fourth quarter of 2019.