The head of Libya's National Oil Corp (NOC), Mustafa Sanalla, ignored a government order sacking him on Wednesday as he returned to Tripoli from Islam's haj pilgrimage, but said he would make a speech later.
The Government of National Unity (GNU) issued a decision on Tuesday to install Farhat Bengdara in place of Sanalla at the head of a new NOC board, raising concerns the state oil producer is being pulled into Libya's political standoff.
Prime Minister Abdulhamid al-Dbeibah also set up a committee to manage the transition to the new board, according to a statement published on the Oil Ministry website.
However, an NOC statement upon Sanalla's return from haj continued to describe him as the chairman and made no mention of the decision to sack him.
Control over Libya's oil revenues through NOC and the central bank has been the biggest prize for warring factions since the 2011 NATO-backed uprising that began years of chaos.
This year the eastern-based parliament has appointed a new government under Fathi Bashagha to replace Dbeibah, who has refused to cede power and remains in control of government ministries in Tripoli.
The power struggle - and questions over the legitimacy of all Libya's political institutions - mean any major national decisions such as replacing the NOC board may prompt broad pushback.
On Tuesday NOC also said it was resuming exports from two ports closed by an oil blockade and hoped to restart other shuttered facilities soon.
However, groups involved in the shutdowns rejected that statement on Wednesday in a video message. The groups had previously demanded that Dbeibah quit in favour of Bashagha and diplomats say they are aligned with eastern commander Khalifa Haftar.
Analysts say the appointment of Bengdara, a central bank governor before 2011 and reputed ally of Haftar, to run NOC may herald an attempt by Dbeibah to shore up his position in Tripoli.
(Reporting by Ayman al-Warfali and Ahmed Elumami, writing by Angus McDowall)