Academic and campaigner Noam Chomsky has said that the US government was relieved that Abdelbaset Ali Mohmed Al Megrahi dropped his appeal, as the legal process would have disclosed material from US intelligence that would have put the safety of Megrahi's conviction in doubt.

"The appeal was going to bring in evidence from US intelligence casting serious doubt on the whole trial,” he said, speaking at the annual Amnesty International lecture in Belfast.

He also said he sympathised with the beleif that the Pan Am 103 event is subject to a politically driven cover-up.

In correspondence to The Firm after the publication of its report which suggested there was sufficient evidence to warrant a fresh investigation into the possibility that the plane may have been destroyed by the accidental detonation of an illicit cargo of munitions components, Chomsky told the Firm he had little faith in the version of events promoted by US and UK authorities.

"The official story about Lockerbie has always appeared to me highly unconvincing, and I think there is good reason to call for a serious independent investigation of the whole affair," he told us.

"I hope that a serious investigation will take place, but the obstacles continue to look more and more daunting."