Libya's state oil company on Sunday called on rival armed factions to avoid damaging the oil terminal in Zueitina, following reports of possible clashes at the eastern port.
The National Oil Corporation (NOC) said it was concerned by reports of "imminent conflict" between the Libyan National Army (LNA) and the Petroleum Facilities Guard (PFG) in the vicinity of Zueitina.
The PFG signed a deal late last month with Libya's U.N.-backed Government of National Accord (GNA) to reopen Zueitina and two other ports that it has been blockading.
The LNA opposes the GNA, and its chief of staff has threatened to target tankers that do not have the approval of a rival government based in eastern Libya.
"I ask both sides to withhold from actions that could damage the infrastructure, including using the facilities as a physical shield," NOC Chairman Mustafa Sanalla said in a statement.
"I also ask both sides to give NOC safe passage now, before any operation commences, to move the oil in storage at the port to a safe location."
Petroleum Facilities Guard spokesman Ali al-Hassi said his force had received threats from the LNA, and that since the announcement that the ports would reopen, groups that Hassi called "rebel gangs" had been targeting Zueitina in a bid to take control of oil terminals and fields.
LNA did not immediately provide a comment.
Fighting, political disputes and militant attacks have reduced Libya's oil production to a fraction of the 1.6 million barrels per day the member of the Organization of the Petroleum Exporting Countries was producing before the 2011 uprising against Muammar Gaddafi.