"Obama is still delusional he believes the lies that his own government and own media spread around the world," government spokesman Mussa Ibrahim told a Tripoli news conference.

"They don't prove one single charge against us and they refuse to investigate us, Ibrahim added.

"It's not Obama who decides whether Moamer Qadhafi leaves Libya or not.

It's the Libyan people who decide their future."

In a major speech responding to the protest movements sweeping the Arab world, Obama had said: "Time is working against Qadhafi.

"He does not have control over his country. The opposition has organised a legitimate and credible interim council," Obama said of the rebels' National Transitional Council based in their eastern stronghold of Benghazi.

"And when Qadhafi inevitably leaves or is forced from power, decades of provocation will come to an end, and the transition to a democratic Libya can proceed."