(Adds Hariga port still closed, background)
By Feras Bosalum and Ahmed Elumami
TRIPOLI, June 15 (Reuters) - Libya's western El Feel oilfield has resumed production after security guards ended a protest that lasted more than two months, oil ministry officials said on Sunday, but many oilfields and ports remain blocked.
The reopening of El Feel is good news for the weak central government struggling with a budget crisis as a wave of protests at oil installations and rebel violence have dried up oil exports, the country's main source of income.
Three years after a NATO-backed revolt toppled leader Muammar Gaddafi, Libya's oil infrastructure remains vulnerable as militias, armed tribesmen and Islamists who helped oust Gaddafi now defy state authority and seize government ministries or oil facilities at will.
Libya's oil output had fallen to less than 200,000 bpd in the past few weeks, down from 1.4 million bpd in July when a wave of protests started.
Much of the remaining output is used to feed the Zawiya refinery which supplies the west of the country. Motorists have been queueing for more than a week to refill in the capital Tripoli with some people sleeping in cars.
Acting Oil Minister Omar Shakmak told Reuters authorities had reached an agreement with protesters. "The protesters agreed to reopen the field which restarted work yesterday and today," he said.
Production at El Feel, located in the southwest, will reach 80,000 barrels a day within 24 hours, said Ibrahim al-Awami, head of the ministry's inspection and measurement department.
Officials did not disclose more details about the agreement with the protesters.
Protesters shut down the field in late March to the western Mellitah port as part of a nationwide disruption to oilfields and ports to pressure the government over a range of political and financial demands.
The field is jointly operated by state-owned National Oil Corp and Italy's ENI and was producing around 85,000 bpd before the shutdown.
HARIGA PORT REMAINS BLOCKED
Libya's eastern Hariga oil export port remained blocked by state security guards who were said they had not been paid for months.
A spokesman for state-oil firm AGOCO, which runs the port and connecting oilfields, said the finance ministry had paid out the salaries but the firm was still waiting for the guards to confirm their protest was over.
Last year, a group of rebels seized Hariga and three other eastern ports with the aim of exporting crude oil from there themselves. It took the government until April to reach an agreement with the rebels to relinquish Hariga and the Zueitina port and to restart exports from there, only for Hariga to be closed again last month by protesting security staff.
The rebels have kept shut the larger Ras Lanuf and Es Sider ports pending further talks with the government. A fourth eastern port, Zueitina, is technically open but there is no currently crude to load.
The 340,000-bpd south western El Sharara field also remains closed. Protesters at the field and connecting pipeline have blocked production several times since October.
El Sharara feeds the Zawiya refinery which now gets supplied by cargoes from Libya's two offshore oilfields, reducing the country's exports.