Mustafa Abedel-Jalil, who resigned on Monday amid violent clashes between protesters and security forces, said: “I have proof that Gaddafi gave the order about Lockerbie.”
Mr Abdel-Jalil, who has not revealed yet what the proof is, quit over the “excessive use of force” used against demonstrators during anti-regime uprisings across the north African state.
The Scottish Government said yesterday it never doubted the safety of the conviction of Libyan Abdelbaset al Megrahi, 58, who was controversially freed from prison on compassionate grounds in August 2009 as he was suffering from prostate cancer.
Megrahi, a Libyan intelligence officer who received a hero’s welcome when arriving in Tripoli, remains alive although some experts believe he only has weeks to live. He is the only man to have been convicted of the bombing of Pan Am flight 103 on December 21, 1988, which killed 270 people.
Yesterday, Mr Abdel-Jalil claimed Colonel Gaddafi personally ordered Megrahi to carry out what remains Britain’s worst terrorist atrocity.
He added: “To hide it, Gaddafi did everything in his power to get Megrahi back from Scotland.”
The revelations have caused outrage coming hot on the heels of leaked diplomatic cables and an official report that showed the former Labour government did “all it could” to help Libya secure the release of Megrahi while ministers professed publicly that the decision on his future was the Scottish Government’s alone.
One cable revealed how Libya was given advice by a Foreign Office minister, Bill Rammell, on how to secure Megrahi’s compassionate release.
Scottish Conservative deputy leader Murdo Fraser MSP said: “Given the events of recent days many people will find this a disturbing but believable claim.
“If true, it makes all the more questionable the role of the last Labour government’s drive to do all it could to send Megrahi back to Tripoli.”
Most of the victims in the Lockerbie bombing were Americans, and Megrahi’s release has been criticised by members of the US Congress and the victims’ families.
Pamela Dix, from the group UK Families Flight 103, who lost her brother Peter in the bombing, said of the latest development: “If this is true, it is shocking. It really rocks to the core the way that the UK Government has dealt with the whole
Lockerbie issue, which is to sweep it under the carpet.
“It is really incredible. I would be really interested to know what evidence he has got. Perhaps he is trying to ingratiate himself with the US.”
Ms Dix also called for a fresh investigation into the bombing in light of the claims.
She said: “If he has really got evidence, the Crown Office in Scotland should investigate. If this is a lead, they should be following this up.”
Lisa Gibson, of Colorado Springs, who lost her brother Ken in the bombing, added: “I’m not surprised for him to say that Gaddafi is responsible because, ultimately, we know that.”
Saif Gaddafi, Colonel Gaddafi’s son, said on Monday that he believed Megrahi was innocent and that his release had no direct links with a trade deal. “One day the whole world will discover the truth about Lockerbie,” he said.
“He (Megrahi) is a very sick man, he has cancer and is in a very serious condition and so it was really immoral for the people to be unhappy with his return to Libya.”
In Britain, some Lockerbie victims’ relatives have questioned his conviction.
They argue that insufficient attention was paid to the possibility that the bombing was carried out not by Libyan intelligence but by Iranian-backed Palestinian terrorists.
Their case was supported when the Scottish Criminal Cases Review Board raised questions about evidence used to convict Megrahi.
The former Libyan agent had been in the process of appealing his conviction when he was released.
If Megrahi was cleared, the Libyans could have claimed back the £1.4 billion in compensation paid to families of the Lockerbie victims -- a bill that could fall to the Scottish Government, being responsible for the justice system.