Britain does not rule out the possibility of arming Libya's rebels, Prime Minister David Cameron said Wednesday.

At the regular Prime Minister's Questions, Cameron told the House of Commons that Libya is an "extremely fluid" situation.

The prime minister told lawmakers Britain must comply with a U.N. Security Council resolution that authorizes necessary measures to protect civilians and imposes an arms embargo.

But he said his legal advice was clear that under the resolution, weapons could be handed to opposition fighters in some limited circumstances.

"We do not rule it out, but we have not taken any decision to do so," Cameron said.

U.S. Secretary of State Hillary Rodham Clinton told an international summit on Libya in London on Tuesday that the U.N. resolution would allow nations to circumvent a current arms embargo.

After Cameron, Foreign Secretary William Hague updated parliamentary members about the London conference on Libya. He said Britain has expelled five Libyan diplomats.

He said, "We have today taken steps to expel five diplomats at the Libyan embassy in London including the military attache," because they could pose a threat to security.