World powers clashed Wednesday over whether it is legal to supply weapons to Libya's badly equipped rebels as Moammar Gadhafi's troops beat back their advance on the ground.
Britain and the U.S. believe that existing U.N. Security Council resolutions on Libya could allow for foreign governments to arm the rebels.
But NATO, which is in the process of taking over command of air and other military operations in Libya, rejected that theory, saying an arms embargo was in place. China, Russia and Germany were also against supplying weapons to the rebels, with Moscow warning of possible al-Qaida links to some rebels.
Analysts, however, suggested the only hope of avoiding a lengthy stalemate in the conflict would be to provide anti-tank weapons and shoulder-launched missiles to the rebels, allowing them to take on Gadhafi's military hardware.
British Prime Minister David Cameron said he supported U.S. Secretary of State Hillary Rodham Clinton's assessment that nations could legally supply weapons to Libyan rebels, despite an arms embargo being in place. Cameron told the House of Commons that U.N. Security Council resolutions "would not necessarily rule out the provision of assistance to those protecting civilians in certain circumstances."
"We do not rule it out, but we have not taken any decision" on whether to supply weapons, he told lawmakers.
Obama said in television interviews Tuesday the U.S. also did not rule out providing arms to rebels, while Clinton said in London that such a move would be legally permitted _ read as a signal the policy is under consideration.
NATO insists the U.N. resolutions prohibit the supply of weapons into Libya, while Russia and China expressed concern that some allies were overstepping the mark. In Germany, Foreign Ministry spokesman Stefan Bredohl said the relevant resolutions included a "comprehensive arms embargo."
Russian Foreign Minister Sergey Lavrov warned Western nations against supplying weapons to Gadhafi's opponents and said Moscow feared that some rebels could be allied with al-Qaida.
His remarks echoed concerns raised in Washington on Tuesday, when NATO's top commander, U.S. Navy Adm. James Stavridis, said officials had seen "flickers" of possible al-Qaida and Hezbollah involvement with the dissident forces.
The comments were seized upon by Michele Bachmann, the tea party-backed conservative congresswoman, who said the U.S. should rule out supplying weapons because of those concerns about an al-Qaida influence.
NATO said agreement from all 28 members of the alliance would be needed to participate in the arming of rebel forces, and that approving such a move would risk further rifts between the members themselves and outside partners such as the Arab League and African Union.
"The U.N. resolution forbids arms to enter Libya," said an official who could not be named under standing regulations. "Quite honestly, NATO wouldn't even consider doing anything else unless a new U.N. Security Council resolution is issued to that effect."
In London, ex-British foreign secretary Malcolm Rifkind urged nations to ensure Libya's rebels are "properly assisted to enable this war to be brought to an end as soon as possible."
British Foreign Secretary William Hague said he supported that view, but also acknowledged that "introducing new weapons into a conflict can have unforeseeable and unknown consequences."
Retired Brigadier Benjamin Barry, of London's International Institute for Strategic Studies, said it wasn't certain rebels would have the ability to use any weapons supplied by the West, because they would likely require basic training.
"The kind of arms that could be provided are simple, easy to use anti-armor weapons, unguided shoulder-launched rockets, guided missiles and mortars," Barry said.
But he acknowledged there would be "a risk that these weapons could pass into unfriendly hands after the fighting is over."
The history of arming anti-Soviet rebels in Afghanistan would weigh heavily on any decision to offer military hardware, Hague said. "There are examples of weapons being given to people in good faith and then those weapons being used for other purposes," he told lawmakers.
Hague confirmed Britain had ordered the expulsion of five Libyan diplomats _ including the country's military attache _ over threats to opponents of Gadhafi's regime in the U.K., and because they posed a potential security risk.
"Were these individuals to remain in Britain, they could pose a threat to our security," Hague said. Officials explained the Libyan diplomats had been involved in attempts to harass opposition supporters in Britain.
Hague said British diplomats had held talks in the eastern Libyan city of Benghazi with opposition figures in recent days _ before similar meetings being held by U.S. and French officials _ to seek assurances about their motives.
He said he was assured that, despite the warning from Stavridis, violent Islamists did not hold a prominent role within Libya's rebel movement.
Slobodan Lekic in Brussels and Jill Lawless in London contributed to this report.