(Adds government spokesman)
By Ulf Laessing
TRIPOLI, March 12 (Reuters) - Former Libyan Prime Minister Ali Zeidan sought refuge in Europe on Wednesday after parliament voted him out for failing to stop rebels independently exporting oil in a challenge to Libya's fragile unity.
The crisis arose when protesters who have seized three eastern ports since August loaded crude onto a North Korean-flagged tanker at Es Sider terminal at the weekend.
The tanker left Es Sider on Tuesday. According to varying accounts by government officials, the navy or air force then fired on the vessel, although it was not clear if this happened in Libyan or international waters.
Government spokesman Habib al-Amin told a news conference in Tripoli that the firing failed to disable the tanker, which proceeded eastwards into Egyptian waters. He said Libya had asked Egypt and other countries to help stop the ship.
There was no independent confirmation of the tanker's whereabouts, destination or ownership.
The debacle underlines the impotence of the authorities in Tripoli, whose fledgling army and police force are no match for the militias and other armed groups who remain a law unto themselves three years after the fall of Muammar Gaddafi.
After the tanker escaped, an infuriated parliament voted out Zeidan on Tuesday and named Defence Minister Abdallah al-Thinni as acting prime minister for two weeks.
Western powers, who supported the NATO campaign that came to the aid of anti-Gaddafi rebels, fear the OPEC member state could slide into greater instability or even break apart, with rival groups laying claim to power and vast oil reserves.
The protesters controlling ports in the east demand autonomy and a greater share of oil resources for their region, which they say was disadvantaged during Gaddafi's 42 years in power.
Led by Ibrahim Jathran, a former anti-Gaddafi fighter, they are drawn from former oil security forces who mutinied last year and took over the oil terminals to press their demands.
Officials said Libya was close to bankruptcy because of the six-month oil blockade, which cost the North African country an estimate $8 billion in lost revenue in 2013, and set a two-week deadline for talks with rebels to end the port seizures before force was used. Similar threats in the past have proved empty.
"We need an emergency budget for the government to carry out its tasks, and to deal with the country's serious security challenges," Thinni told reporters.
After flying out of Libya, Zeidan made a two-hour stopover in Malta before going to "another European country", Maltese Prime Minister Joseph Muscat told state-owned television TVM.
Government sources in Malta said Zeidan had left on a private plane for Germany, but authorities in Germany and other European countries have not confirmed his whereabouts.
DANGER OF BANKRUPTCY
Libya's transitional assembly, the General National Council, said it would pick another replacement for Zeidan within two weeks before a parliamentary election expected later this year.
Whoever is chosen will struggle to govern a country deeply divided on tribal, regional and political lines, where hardline Islamists oppose more liberal leaders such as Zeidan.
"We are new to this political game. We are still learning," said Salah Elbakhoush, a Tripoli-based political analyst.
Libya has lurched from crisis to crisis since Gaddafi fell in 2011 after an eight-month civil war. Many Libyans are frustrated by the chaos and violence undermining what had been planned as a transition to democracy.
The government is in danger of running out of money because rebel activity at oilfields and ports has cut oil production to below 300,000 barrels per day from 1.4 million bpd last year.
Powerful groups of former rebels and militiamen often step into the vacuum in a country still awash with arms from Gaddafi's days and the revolt that ended his rule.
The Misratan militia, based in the port town of Misrata and loosely allied with Islamist parties in the GNC, has gathered forces to support the government and confront the armed protesters who have seized oil terminals in the east.
But analysts said a rival militia based in the northwestern mountain town of Zintan was unlikely to let the Misratans grab a larger security role in Libya without reacting themselves.
How such conflicts will play out is unclear, with alliances often shifting in a network of interlacing disputes. In the latest violence, clashes broke out on Tuesday between rebels and pro-government forces in the central coastal city of Sirte.
"With control of the central government and Libya's oil at stake, all of these groups, rivalries, and alliances of convenience are coming to the fore," said Geoff Porter, North Africa specialist at West Point's Combating Terrorism Center.
"One of the reasons that Libya has reached this impasse is that dialogue had failed, not least because there was no one in Libya that could speak authoritatively and had the capacity to translate words into action."
(Additional reporting by Chris Scicluna; Writing by Patrick Markey; Editing by Alistair Lyon)