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BENGHAZI, Libya, Jan 7 (Reuters) - A pro-autonomy group in eastern Libya is inviting foreign companies to buy oil from ports it had seized bypassing the central government, its co-leader said on Tuesday, escalating a conflict with Tripoli.
On Monday, Libya's navy said it had fired shots at a Malta-flagged tanker which it said had tried to load oil at the eastern Es-Sider port which has been seized by the pro-autonomy group.
The group denied it had anything to do with the ship but said it would go ahead with its plans to sell oil on its own, despite warnings by Tripoli to attack any tankers.
"We welcome global oil companies ... The oil security guards will guarantee the safety of tankers," said Abd-Rabbo al-Barassi, prime minister of the self-declared eastern government which has a heavily armed militia force.
Workers at the seized ports had returned to work, he said, adding that its newly founded oil company would be dealing with potential buyers.
But Barassi, speaking on a pro-autonomy television station late on Tuesday, said his group had no plans to break up Libya despite the conflict with the Tripoli government.
"We confirm we want to preserve Libya's territorial unity," he said, adding that it invited Tripoli to send a delegation to help oversee the proper sale of oil sales "according to the law".
The group is campaigning for a federal state sharing power and oil wealth between the eastern Cyrenaica, the west and southern Fezzan.
Its fighters were part of a rebel group which helped topple Muammar Gaddafi in 2011 but kept its guns, like dozens of other militias, to pressure the weak government into its demands. (Reporting by Ghaith Shennib, Ulf Laessing and Ayman al-Warfalli; editing by Gunna Dickson)