"One of the biggest risk factors in this was our lack of understanding of the people we were working with, and I think that lack of understanding still stands," he said.
Bob Stewart, the Tory MP and former British United Nations Commander in Bosnia, said he feared the Libyan conflict would end with "a government we don't like and us getting the blame".
Labour MP John McDonnell called for a peace conference between Gaddafi and the rebels to be enforced: "The Government are treading on a path that is extremely uncertain. They are dealing with people of whom they have very little knowledge and this is just an example of the potential there is for disunity."
In Tripoli, Gaddafi's spokesman, Moussa Ibrahim, took the opportunity to mock British support for the rebels, declaring: "It is a nice slap [in] the face [for] the British that the [rebel] council that they recognised could not protect its own commander of the army."
Ibrahim alleged al-Qaeda elements were behind the killing, stating "by this act, al-Qaeda wanted to mark out its presence and its influence in this region".
As the news emerged yesterday, former British Liberal Democrat leader Lord Paddy Ashdown urged the Government not to change its policy. "We are obviously not in the best place we could be, but this is what you have got to expect," he said. "If you want to do this according to international law, this is what it looks like. This is messy, this is unpleasant and inelegant to watch, but it is no worse than doing it ourselves."
Younis was killed in mysterious circumstances on Friday. Initially, Mustafa Abdul Jalil, president of the National Transitional Council, the rebel's government, claimed the murder had been carried out by Gaddafi-linked forces. That was starkly contradicted yesterday by oil minister Ali Tarhouni who confirmed Younis had been killed by members of the Obaida Ibn Jarrah Brigade, a group linked to the rebels.
Tarhouni said Younis was being brought back to Benghazi when he was shot. A militia leader who had gone to fetch Younis from the front line had been arrested and confessed that his subordinates had carried out the killing.
"It was not him. His lieutenants did it," Tarhouni said, adding that the killers were still at large. The Foreign Office was seeking confirmation from Jalil over the claim.
The authorities have yet to say where Younis was killed, or when, or how his body vanished for 24 hours. Neither is it clear why he was being brought back to Benghazi.
Reports in rebel-controlled Libya also contradict the official version, with radio stations reporting Younis was killed not on the road but after being kidnapped in a hotel room in the rebel capital and that the general had been under arrest that morning, accused of holding secret talks with Gaddafi regime officials.
Adding to the sense of crisis engulfing Libya's rebels yesterday, Gaddafi launched his heaviest assault yet on Misrata using tanks, infantry and artillery against rebel front lines.
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