Tripoli - Oil output from Libya, where ports and oilfields have been shut due to fighting, has fallen to 363 000 barrels a day with exports at about 200 000, the oil minister appointed by forces in control of the capital Tripoli told Reuters.
Two governments allied to armed factions are vying for control of Libya four years after the toppling of leader Muammar Gaddafi.
The United Nations and Western powers do not recognise the administration which controls ministries in Tripoli.
Its oil minister, Mashallah Zwai, told Reuters in an interview that Libya is producing 362,780 bpd of oil, showing a report from the National Oil Corporation.
That is down by half from November, when Opec member Libya was producing around 750 000 barrels a day, and well below the 1.6 million which the North African country produced in 2010.
Zwai said oil revenues would fall to between $10 billion and $12 billion this year after slumping to $15 billion in 2014 when Libya suffered a budget deficit of $19 billion.
Output has fallen since facilities such as the El Sharara oilfield and the ports of Ras Lanuf and Es Sider were shut down due to nearby clashes or pipeline blockages.
Foreign oil buyers have been confused over who is in charge since a faction called Libya Dawn took over the capital in August, forcing Libya's recognised prime minister and elected assembly to move to the east of the country.
Zwai works in the old minister's Tripoli office in a building which also houses the NOC.
He said some 150 000 bpd of crude was being used for domestic refineries and that the biggest one in Zawiya was producing 110 000 bpd, just 10 000 short of its maximum capacity.
He said the biggest contributors were Arabian Gulf Company (AGOCO) which was producing 131 547 bpd from fields in Libya's far east and the Hariga port which has largely escaped the violence gripping other parts of the country.
The Sirte Oil Company is producing 54 000 bpd through the eastern port of Brega to supply the Zawiya refinery, the NOC figures showed.
Libya's conflict also involves tribal loyalties, federalist movements and rival political groups often allied to their cities or regions.
That has complicated UN efforts to bring the recognised government of Prime Minister Abdullah al-Thinni and Libya Dawn fully into negotiations in Geneva over a unity government. Talks are due to restart on Monday.
Zwai said his government wanted to keep the conflict out of state firm NOC by retaining a decades-old payment system through the country's Tripoli-based central bank. All contracts with oil firms would be honoured, he said.
The Thinni government has announced plans to set up new bank accounts in the eastern region in a bid to control the flow of oil revenues.
Zwai said such a move risked breaking up Libya.
“If they want partition we are ready for this, but we don't want partition because we are thinking of Libya's interest,” he said.
The minister also warned that his tribe, the Zwaiya, was in control of major oilfields in the east should a federalist movement allied to Thinni's government push for partition of that region.
“If they want partition I have a clear message: we the Zwaiya tribe own all oil ports and resources (in the east) which we won't allow to get broken up,” he said.
Zwai said 500 000 barrels of oil was destroyed after a rocket struck storage tanks at Es Sider in December, leaving three millions of barrels still stored there.
That is lower than a loss of up to 1.5 million barrels estimated by eastern officials.
Oil guards loyal to Thinni have prevented the administration in Tripoli from lifting the two million barrels ready for shipment from the tanks.
Each side has blamed the other for the rocket strike.
Reuters