THE new Libyan Government has admitted for the first time that Abdelbasset Ali Mohmed al Megrahi was involved in the Lockerbie bombing, which claimed the lives of 270 people.

Ashour Shamis, adviser to the country's Prime Minister Abdurrahim al Keib, scotched the theory the only man convicted of the atrocity was the victim of a miscarriage of justice.

Mr Shamis claimed that, as a security adviser to Colonel Gaddafi, Megrahi would have had a part to play.

While the new Government in Libya has maintained Gaddafi executed the terror attack, it has never before pinpointed the involvement of Megrahi.

Mr Shamis made the admission to Dr Jim Swire during a trip to Tripoli which was filmed for a documentary to be screened tonight on STV.

Dr Swire, 75 – whose daughter Flora died in the bombing of Pan Am flight 103 in 1988 – has long believed in the convicted bomber's innocence and he told filmmakers of the guilt he feels for pressing Libya to hand Megrahi over to stand trial.

He went to Libya to continue his search for the full truth behind Lockerbie and to say goodbye to Megrahi, who is suffering from terminal prostate cancer.

As his fact-finding mission unfolded in Tripoli, he met Mr Shamis after being granted an interview with the Government.

Mr Shamis said: "As far as the Libyans are concerned, the Gaddafi regime, Gaddafi personally, are involved in planning and executing this atrocity.

"There is no doubt about it They are involved. The regime are involved."

He said Gaddafi's payment of compensation to victims was proof the despot, who was killed in the rebel uprising in October, was behind the terror attack.

Backers of Gaddafi have always maintained the money was paid to force the lifting of UN sanctions against Libya.

Crucially, Mr Shamis added that Megrahi was involved in the bombing even if "he was only a small player". He said: "Megrahi is an employee of Libyan security, there is no doubt about it – of external security. And if he was told to do something he would have done it."

Megrahi was convicted of the mass murder in 2001 and spent eight years in a Scottish prison before being released from HMP Greenock due to his diagnosis of terminal prostate cancer.

Despite being given three months to live at the time of his release, he is still alive in his family compound in Tripoli.

Megrahi forfeited his appeal against conviction by choosing to return home on compassionate grounds.

In the documentary, Dr Swire elaborated on the guilt he feels over Megrahi's time in prison, describing him as a "decent guy". Dr Swire said: "I feel a sense of guilt about Megrahi ever being found guilty because maybe, just maybe, if I hadn't tried as far as I did, maybe Gaddafi wouldn't have handed him over because it was Gaddafi that I addressed my pleas to – to allow him to be handed over.

"So I feel guilt towards Megrahi, he is a decent guy and many other people who have met him said the same sort of thing.

"I doubt now, that he was a member of Libyan intelligence at all and I don't think he knows who in the Libyan regime knew what was going on.

"That of course brings us to the question of how much did the Libyan regime know and what can we find out."

Dr Swire visited Megrahi during his recent trip but camera crews were banned during the meeting. He was described as "distraught" following the pair's hour-long encounter.

Dr Swire said: "I think that what happened - in the sick room of a dying man and his doctor has to remain private.

"He is a very sick man and I thought it was a privilege to have been allowed essentially to say goodbye to him."

Dr Swire, who had met Megrahi previously, added: "This is a different and deeper level than we have been at before ... this was a parting discussion between two people who know each other, one of whom is going to die in the very near future."

l Tonight: Did Gaddafi Kill My Daughter? stv at 7.30pm.