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By Feras Bosalum and Ulf Laessing
TRIPOLI, April 1 (Reuters) - A rebel group in eastern Libya has agreed with the government to end its seizure of vital oil export ports within days, a senior leader told Reuters on Tuesday, raising hopes to end an eight-month stalemate drying up state income and fuelling chaos.
There was no immediate comment from the Tripoli government which has been trying since summer to end the seizure of three eastern ports, which previously counted for more than 600,000 barrels of day.
The oil conflict is just one aspect of the turmoil in the OPEC producer where the weak central government is unable to control dozens of militias who helped topple Muammar Gaddafi in 2011 but refuse to disarm and are trying to grab a share of power or oil wealth.
Talks with the eastern rebels had moved forward after the U.S. navy captured a tanker that had loaded oil at a rebel port, killing hopes of its leaders to sell crude bypassing Tripoli and pressuring them to agree on a deal.
The government had earlier met a rebel demand by releasing three of its fighters which had boarded the tanker at Es Sider, one of three ports seized by the group in August to press for autonomy and a greater share of oil wealth.
"The oil port issue will be solved within days," Abb-Rabbo al-Barassi, self-declared prime minister of the rebel group, said. "We agreed on all issues with the government in Tripoli."
A government delegation would visit the group's home base Ajdabiya in eastern Libya within two days to hammer out the details, he told Reuters by phone. He gave no details.
The group's top leader Ibrahim Jathran had minutes earlier told a rebel television station in a conciliatory speech his group had reached a solution benefiting the people of Cyrenaica, the east's historic name, and "all honorable Libyans".
"This agreement will upset all those who don't want the good for Libya and its people but it will make happy all national thinking Libyans. That's important for us. That's what we strive for," Jathran said in a speech lasting eight minutes.
He gave no details or date but swapped his often martial tone with a much more conciliatory tone, addressing "all Libyans" and stressing dialogue and the need for stability.
Jathran repeated the rebel demands for giving the east a share of oil and combatting oil corruption but also talked about reaching out to all regions and cities to build a stable Libya.
Western powers worry the conflict over oil will fuel instability or even break up the vast desert country as many in the east complain of decades of neglect at the hand of western cities such as the capital Tripoli or the main port Misrata.
Jathran mentioned his group's strive to reinstate the 1951 constitution from the era of King Idris, who had preceded Gaddafi, and introduced in a federalist system sharing power between regions.
But compared to other speeches, Jathran focused this time of dialogue. "This night I'm addressing the people of Libya as a whole to talk about some truths and announces some joyous issues not only for Cyrenaica but the whole of Libya."
Jathran, a rebel commander who fought Gaddafi during the 2011 civil war, did not mention a previous demand to the government to return the oil tanker.
Still, markets are likely to meet his comments with some scepticism after a similar deal fell through in December at the last minute.
With no real army, Libyan authorities are struggling to control militias and armed tribesmen who help to oust Gaddafi in the 2011 civil war but have become political players controlling territory.
On Monday, Libya's attorney general ordered the release of three rebel fighters in a gesture to the rebels.
Three weeks ago, the rebel militia embarrassed Tripoli by loading crude onto the "Morning Glory" tanker. U.S. special forces later stormed the ship in international waters and returned it to Libya.
Government and the parliament had told the militia to negotiate an end to their port blockade or face a military offensive.
But government officials and key lawmakers have stopped talking for more than a week of any military action, paving the way for more talks.
The army would have struggled to tackle Jathran's forces anyay as they are battle-hardened from the civil war.
His forces and other militias refuse to surrender their weapons and often use force or control of oil facilities to make demands on a state whose army is still in training with Western governments.
Those governments, which backed NATO air strikes to help the 2011 anti-Gaddafi revolt, are pressing the factions to reach a political settlement. But Libya has lurched from crisis to crisis over the last year.
Libya's oil production has fallen to a trickle due to the port seizures and protests at major oil fields, forcing the central bank to burn foreign exchange reserves. (Reporting by Ulf Laessing, Ayman al-Warfalli and Feras Bosalum; editing by Andrew Roche)