Libya's top oil official defects - Tunisian source

TRIPOLI/TUNIS (Reuters) - The chairman of Libya's National Oil Corporation has defected from Muammar Gaddafi's administration and fled to neighbouring Tunisia, a Tunisian security source said on Tuesday.

Libyan rebels also said they had information that Shokri Ghanem, 68, had defected, a move that if confirmed would deal a major blow to Gaddafi's efforts to shore up his 41-year rule.

"He is in a hotel with a group of other Libyan officials," the Tunisian source told Reuters, saying Ghanem had been staying in the south of the country. Another Tunisian security source said he was on his way to the capital Tunis.

A government official in Tripoli said there was no sign Ghanem had defected.

Three months into the unrest, rebels hold Benghazi and the oil-producing east of Libya, helped by a NATO bombing campaign sanctioned at the United Nations to protect civilians.

But the military victory rebels once sought seems a distant prospect and many pin their hopes on a collapse of central power in Tripoli driven by disaffection and defections.

Ghanem, an internationally respected technocrat, is credited with liberalising Libya's economy and energy sector.