By Stephanie Nebehay and Tom Miles
GENEVA (Reuters) - The top United Nations official in Libya called on Tuesday for countries to support the fledgling national unity government of the North African country and do more to halt banned arms shipments there.
U.N. envoy Martin Kobler also cited "positive signs" of management of Libya's oil sector and in ensuring that revenues go into the central bank's coffers.
But Libya remains plagued by corruption and an absence of the rule of law, marked by "abominable" state-run detention centres holding migrants trying to reach Europe, he said.
The fall of dictator Muammar Gaddafi in 2011 brought chaos that splintered Libya into rival armed fiefdoms. A U.N.-backed Government of National Accord has been trying for months to extend its authority beyond its base in Tripoli in western Libya.
"It is very important that the international community maintains cohesion in order to bring the Government of National Accord to a stage where it can effectively combat the questions on the table," Kobler told reporters after addressing the U.N. Human Rights Council in Geneva.
General Khalifa Haftar, who has been waging a military campaign against Islamists and other opponents in Benghazi and the east, has been in a stand-off with the GNA for months, blocking a parliamentary vote to endorse the GNA and challenging the U.N.-mediated deal to unify Libya.
Kobler said Libya had 26 million weapons and a population of 6 million. All U.N. member states must respect the arms embargo - with no guns going to either side, he said.
"My position here is very clear. These weapons do not fall from the sky, they come via the sea, they come via land."
Neighbouring countries in particular had an interest in preventing any spillover of the conflict, he said.
"This is of course Europeans, but this is also Egypt, Algeria, in particular the south. There is a link between the terrorism in Libya and with Boko Haram in the south."
But the fact that Libya had one national oil company and one central bank, with slowly rising oil production, was a positive sign.
Libya's Arabian Gulf Oil Company (AGOCO), a subsidiary of the National Oil Corporation, has raised its production to 261,000 barrels per day - 50,000 bpd higher than its output last week, spokesman Omran al-Zwai said on Monday.
"This is the lifeline for the Libyan people, that more money comes into the coffers of the central bank in order to improve the imports and to finance salaries and other basic needs and services for the population," Kobler said.
(Editing by Hugh Lawson)