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TRIPOLI/LONDON, March 5 (Reuters) - A North Korean-flagged oil tanker tried to dock at Libya's Es-Sider oil port seized by armed protesters demanding more autonomy from the government, the Libyan navy and oil officials said on Wednesday.
The tanker Morning Glory approached the port on Tuesday but later left, navy spokesman Ayoub Qassem and officials at state-owned National Oil Corp (NOC) said.
NOC has declared force majeure at the port and warned any tankers against approaching as the Es-Sider terminal is under the control of protesters who have said they might try selling oil bypassing the Tripoli government.
It was not immediately clear whether those on the ship tried to buy oil from protesters but any attempt to get crude to world markets independently would be an escalation of the blockade that has slashed Libya's vital oil exports.
It is extremely unusual for a North Korean-flagged oil tanker to operate in the Mediterranean region, according to shipping sources.
Libya's government has tried to end a wave of protests at Es-Sider and two other eastern oil ports but talks with armed men demanding a greater share of oil and political autonomy have made little progress.
"The navy spotted a tanker from North Korea trying to enter Es-Sider port but it left," Qassem said, confirming information from oil and shipping sources.
Control room workers at the port still loyal to the state oil company told the tanker not to dock as it did not have a contract with NOC, several oil officials said.
"The tanker came to Es-Sider but did not load oil," said an official at state-owned Waha Oil Co which operates the ports and connecting oilfields.
The vessel was still circling near the port on Wednesday, Reuters AIS Live ship tracking showed. It arrived in the area after sailing through the Suez Canal.
In January, the Libyan navy opened fired on a Maltese-flagged tanker which it said had tried to load oil from the protesters in the port.
Former militia commander Ibrahim Jathran with thousands of his troops seized the Es-Sider, Ras-Ranuf and Zueitina ports in east Libya in the summer to press his political and financial demands on the central government.
Libya is struggling with armed groups and tribesmen who helped topple Muammar Gaddafi in 2001 but kept their weapons.
Oil output has fallen to little over 200,000 barrels per day from 1.4 million bpd in July when protests started across the country, depriving the OPEC producer of its main budget source. (Reporting by Ulf Laessing, Julia Payne and Feras Bosalum, editing by David Evans)