Nato has begun 24-hour aerial surveillance over Libya as it weighs up its options for preventing further bloodshed in civil-war ravaged country.

Meeting in Brussels, military chiefs from the US, France and Britain stepped up the debate on imposing a no-fly zone which might help loosen Colonel Gaddafi’s 41 year hold on power.

In Washington, the White House confirmed that NATO is debating a “wide range” of options in Libya which included providing arms to the rebels opposing Gaddafi.

However Arab Gulf nations and U.K Foreign Secretary William Hague favour a no-fly zone and will be identifying “clear triggers” – ie gross human rights violations – for the UN to ground Gaddafi’s air force.

The plans will be presented to defence ministers from the alliance’s 28 member states in Brussels on Thursday.

The possible resolution would be subject to a vote by the 15 members of the UN Security Council.

Russia and China, who generally oppose military intervention, could be sticking points.

The discussions come amid reports that Libyan warplanes have bombed opposition positions in the oil port of Ras Lanouf in Libya’s east.

“An air strike hit a house in a residential area of Ras Lanouf. There is a big hole in the ground floor of the two-storey home,” one witness told Reuters. “A massive plume of smoke and dust flew up in the area from the strike. Men rushed to the area shouting ‘Allahu Akbar’ [God is great].”

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