The Libyan man convicted of the Lockerbie bombing and a victim’s father have accused a Maltese witness at the centre of the probe of “betraying a fellow human being for money”.

Jim Swire, whose daughter Flora was killed in the 1988 bombing of the Pan Am aircraft, spoke exclusively to The Sunday Times just days after meeting Abdelbaset Al-Megrahi, who was convicted of killing 259 people on board and 11 on the ground.

The two men met in Tripoli last Tuesday where they discussed, among other issues, Tony Gauci, the owner of a shop in Sliema who claimed he had identified Mr Al-Megrahi as the man who had bought clothes from him that were later found wrapped around the bomb.

His testimony led to the imprisonment of Mr Al-Megrahi, until the Libyan was controversially released a year ago on compassionate grounds after being diagnosed with advanced prostate cancer.

When asked whether the two men spoke about Mr Gauci’s testimony, Dr Swire said: “Yes we did. We felt that if Abdelbaset and I were standing at the gates of heaven, and Mr Gauci applied for entry he would be asked why he had betrayed his brother human being and his only answer would have to be ‘for the money’.”

Mr Al-Megrahi’s defence team recently contended that the Maltese witness was paid “in excess of $2 million”, while his brother was paid “in excess of $1 million” for their cooperation. Neither has ever denied receiving payment.

Twenty-two years on from the bombing, Dr Swire remains convinced of the Libyan’s innocence, saying he was converted by the evidence he heard in the main trial at Camp Zeist.

“Everything I have heard since has reinforced that view, particularly the Heathrow break-in, knowledge of which was denied to the court and of course hidden from us, until after the verdict had been reached.”

Dr Swire said Mr Gauci’s evidence was clearly unreliable now that it had emerged (from a policeman’s diary, since made public by Mr Megrahi’s defence team and not seen by the court), that he was enticed with offers of American money to give evidence, which the court was unaware of.

Malta was implicated in the case because the prosecution said Mr Al-Megrahi had originally placed the unaccompanied bomb on an Air Malta flight.

It was argued the suitcase containing the bomb was then transferred at Frankfurt airport onto a feeder flight to London and then at Heathrow onto the Pan Am plane flight, PA103, that later exploded over Lockerbie in Scotland 38 minutes after take-off.

Mr Al-Megrahi was said to be a secret service agent for the Libyan government stationed in Malta with Libyan Arab Airlines.

Dr Swire said that evidence from a man who worked at a cafe at the former Luqa airport had claimed that a Scottish detective had suggested he might “refresh his memory” by remembering that if he produced evidence against the Libyan he would be likely to get enough money to allow him to travel abroad.

Both Mr Al-Megrahi and Dr Swire believe there was political interference in the case.

“If there really was direct interference either by those involved in the investigation, or by other arms of intelligence communities to achieve a politically ‘desirable’ verdict, the host nations would hardly welcome an exposure of their collusion to pervert the course of justice, even after 21 years,” Dr Swire said.

Some arguments against the conviction

• Air Malta was able to prove that all 55 bags loaded onto the flight to Frankfurt were ascribed to passengers.

• Claims that there was a break-in at Heathrow fits perfectly with the theory that a Syrian group was behind the bomb which downed the aircraft. Their bombs were known to be stable at ground level, but if put into an aircraft they would always explode between 35 and 40 minutes after take-off, thanks to an internal timer only being triggered by a drop in air pressure. The Lockerbie aircraft flew for 38 minutes before exploding.

• An FBI agent held up in front of US public television cameras a photograph of a timer circuit board through which he claimed to have linked the crime to Libya. Critics said the photograph was of a circuit board which had not been involved in proximity to any explosion. Court evidence later confirmed that the CIA had already been in possession of timers containing such circuit boards.

• A book had claimed that the Syria-based Popular Front for the Liberation of Palestine-General Command (PFLP-GC) had received $10 million or so from Iran immediately after Lockerbie. The PFLP-GC appears to have acted as a mercenary, or executive in carrying out the wishes of the Iranian Ayatollahs in revenge for the erroneous US downing of an Iranian aircraft.

• There are political reasons why the US had wanted to take the heat off Iran and Syria at the time. The return of US hostages held by Iranian backed groups was still on the agenda at the time.

• A US intelligence team who had been investigating the hostage dispositions in Lebanon were among those on the doomed PA103. Their leader’s bag had been cut open by hand and some of its contents removed before it was returned to the crash site for the Scottish police to find. This interference with the evidence chain was known to the court which placed no emphasis on it.

• The court never ordered the production of the diaries pertaining to a detective involved in the complex forensic investigation into the bombing even though they knew of their existence. These exposed serious backhand dealings and showed that the Maltese witness was interested in the awards being offered by the US ‘Rewards for Justice’ programme provided he gave evidence leading to Mr Al-Megrahi’s conviction.