Ibrahim Jathran, who wants more autonomy from Tripoli for his eastern region, had agreed with Maiteeq's predecessor to steadily end the protests, which have cut the OPEC member country's oil exports after the ports fell under his control last summer.
Jathran's statement added to the opposition to Maiteeq, a businessman backed by the Muslim Brotherhood, who was appointed two weeks ago in a chaotic, parliamentary vote that prompted anti-Islamist factions to challenge his legitimacy.
Libya's parliament, the General National Congress, has been paralyzed by infighting among pro- and anti-Islamist, tribal and regional factions vying for influence in the chaos that followed the 2011 uprising against Muammar Gaddafi.
"All options are on the table," Jathran said, without a direct reference to the oil accord. "If the parliament keeps with its decision on the new government, then we will take a different position than we have before."
Keeping ports closed will be a blow to Maiteeq's new government, with the country's oil production down to 160,000 barrels per day (bpd) compared with 1.4 million bpd because of the Jathran blockade and other pipeline protests.