"There is reason to believe that the majority of the oil and gas fields are no longer under Qadhafi's control," Gunther Oettinger told a news conference following a regular meeting of EU energy ministers.

Oettinger dismissed the idea of imposing a blockade on oil exports from Libya because the installations are now in the hands of regional groups opposed to the Qadhafi government.

"We would potentially be punishing the wrong people," he said.

The EU agreed earlier slapped an asset freeze and a travel ban on Qadhafi and 25 members of his family and inner circle, and banned the supply of weapons, ammunition and related material to Tripoli.

The 27-nation bloc finalised the measures after the UN Security Council agreed at the weekend to impose sanctions on the Qadhafi regime in a bid to stem the deadly repression of an opposition movement.