This file photo taken on November 20, 2010 shows British Prime Minister David Cameron speaking during a press conference in Lisbon. Cameron told Libya leader Moamer Gadhafi that it was “time to go”, saying there was no role for the long-serving ruler in the troubled country's future. -AFP Photo

LONDON: Prime Minister David Cameron said Monday he's ordered his top brass to work with Britain's allies on a plan to establish a military no-fly zone over Libya.

Cameron did not say whether that meant that the UK and its allies were preparing to enforce such a flight ban or simply making plans in case the situation there escalated.

But he told British lawmakers that ''we do not in any way rule out the use of military assets'' to deal with Moammar Gadhafi's embattled regime, which has attempted to crush pro-democracy protests with intense violence.

''We must not tolerate this regime using military force against its own people,'' Cameron said. ''It is clear that this is an illegitimate regime that has lost the consent of its people. My message to Col. Gadhafi is simple: 'Go now.'''

The international community already has moved to impose an arms embargo, visa bans and other sanctions on the Libyan government, part of an escalating global effort to halt his crackdown.

Negotiating the approval of a no-fly zone at the United Nations would be complex, but calls for the imposition of such a ban are growing.