"The SAS are very use to working in small groups and they are the type of force that would be ideally suited to this sort of role. But we have to beware of mission creep."
Another defence source, speaking anonymously, said: "History has shown us that air power alone will not win campaigns.
"In the first Gulf War, Bosnia and Kosovo, air power played a vital role but a ground force was needed to achieve the mission. So the question for the UN is what to do next? It is clear now that some sort of ground campaign is needed.
"The question is, who should lead the ground campaign? The rebels do not have the capability, by using privatemilitary companies you run the risk of being accused of hiring mercenaries and under whose mandate would they operate?
"So the responsibility will fall to the UK, the US and France. Libya is heading for a bloody civil war and who ever leads the ground force will find themselves in the middle of it."
