Lord Fraser of Carmyllie, the former Lord Advocate who oversaw the issue of indictments in the Crown's discredited case against Abdelbaset Ali Mohmed Al Megrahi, has conceded that the key prosecution witness in the Lockerbie trial was bribed for his testimony.

"I have to accept that it happened," Fraser told Al Jazeera.

"It shouldn’t have and I was unaware of it.”

Fraser now says the payment of "bribes, inducements or rewards" is unacceptable, and "it is obviously unacceptable to have done it in the biggest case of mass murder ever carried out in Europe.”

It has long been known that a Maltese shopkeeper Tony Gauci, who provided a hedged and circuitous identification of Megrahi, was later paid for his testimony by US authorities. Fraser's admission represents the first confirmation that Gauci was offered inducements as early as September 1989, ahead of his testimony.

Gauci's testimony stated that Al Megrahi was the purchaser of items of clothing in Malta, fragments of which were later found attached to pieces of circuit board linked to a timer that was claimed to have detonated in Pan Am 103.

That version of events has been widely discredited and claimed to be scientifically implausible.

Seperately, former MEBO employee Ulrich Lumpert swore an affidavit in June 2007 that he had fabricated the circuit board fragment and handed it to authorities investigating the Pan Am 103 event. He conceded he perjured himself during the Zeist trial.

"I...warned our investigators that the eyes of the world were on us, and everything had to be done by the book," Fraser says.

"It would be unacceptable to offer bribes, inducements or rewards to any witness in a routine murder trial in Glasgow or Dundee, and it is obviously unacceptable to have done it in the biggest case of mass murder ever carried out in Europe.”

The Holyrood petitions Committee will shortly hear a submission from the Justice for Megrahi campaign group to open an inquiry into the affair.