The head of the British armed forces has said Nato must intensify its military campaign in Libya by easing the restrictions on bombing targets.
General Sir David Richards told the Sunday Telegraph direct attacks should be launched against the infrastructure propping up Colonel Gaddafi's regime.
He said it was necessary to prevent the Libyan dictator remaining in power.
The UK and other countries have been bombing Libya under a UN resolution authorising force to protect civilians.
The Security Council resolution authorises "all necessary measures" to protect civilians under threat of attack - short of an occupying force.
The views of Gen Richards, Chief of the Defence Staff, are said to be supported by other senior Nato officers.
They argue increasing the range of targets from direct threats such as tanks and command sites would be legitimate, but would require the backing of member states.
Col Gaddafi's removal is not a specified military objective of the action.
But in the interview with the Telegraph, Gen Richards said it would be "within the rules" should he be killed in a strike on a command and control centre.
He said the "vice is closing on Gaddafi but we need to increase the pressure further through more intense military action".
He said: "The military campaign to date has been a significant success for Nato and our Arab allies. But we need to do more.
"If we do not up the ante now there is a risk that the conflict could result in Gaddafi clinging to power.
"At present, Nato is not attacking infrastructure targets in Libya. But if we want to increase the pressure on Gaddafi's regime then we need to give serious consideration to increasing the range of targets we can hit."
Gen Richards added there had been "hardly any civilian casualties as a result of the extreme care Nato has taken in the selection of bombing targets".
His comments come as a Nato official said it was aware of Libyan state media reports that as many as 11 clerics were killed in its strike on the town of Brega but insisted that a "clearly identified" military command and control site had been targeted.
Meanwhile, Col Gaddafi has taunted Nato troops in an audio message on state TV, saying he was in a place where they "cannot reach" him.