The pressure on Gordon Brown over the UK's dealings with Libya has intensified after Colonel Muammar Gaddafi's son said there was an "obvious" link between their trade talks and efforts to release the man convicted of the Lockerbie bombing.
The Tory leader, David Cameron, led a chorus of opposition complaints after Saif Gaddafi said it was "not a secret" that Libya's oil and trade talks with the UK were linked to its efforts to get Abdelbaset al-Megrahi, jailed in 2001 for planting the bomb that killed 270 people, returned to Libya.
The Tories, Liberal Democrats and senior SNP MPs said Brown now had to disclose all the details about ministerial meetings and dealings with the Libyan regime before Megrahi was released last week by the Scottish government.
Saif Gaddafi attempted to dampen down the row by insisting that the prisoner transfer agreement signed by Tony Blair in 2007 ultimately had no bearing on the decision by Scottish ministers to free Megrahi, who is close to death with prostate cancer, on compassionate grounds.
The prisoner transfer agreement (PTA) "was one animal and the other was the compassionate release," he told the Herald newspaper. "They are two completely different animals. The Scottish authorities rejected the PTA. It did not work at all, therefore it was meaningless. He was released for completely different reasons."
Gaddafi added, however, that although Megrahi was never mentioned by name when the trade deals and prisoner transfer deal were being negotiated, "it was obvious we were talking about him. We all knew that was what we were talking about. People should not get angry because we were talking about commerce or oil. We signed an oil deal at the same time. The commerce and politics and deals were all with the PTA."
Even so, Gaddafi said there was "zero link" between Megrahi and his meeting with the business secretary, Lord Mandelson, in Corfu. But Cameron suggested the clear association between the prisoner transfer agreement and trade deals raised questions about the ethics of ministers.
The Tories would table parliamentary questions pressing for answers when Westminster returns from the recess, Cameron said. "The real questions remain unanswered. To begin with, what dealings has his government had with that of Libya on this issue?"
"And most importantly of all, what is Gordon Brown's opinion of the decision to return Mr al-Megrahi on compassionate grounds? I have made my view clear. I think it was wrong. I see no justice in affording mercy to someone who showed no mercy to his victims."
The BBC released a poll showing 60% of Scots opposed Megrahi's release on compassionate grounds and 74% believed it had damaged Scotland's reputation. The same BBC poll said 68% of Scots also thought it had harmed Brown's standing.
Scottish government officials in Edinburgh said neither the first minister, Alex Salmond, nor his industry ministers had had discussions about Libyan oil deals with any Scottish businesses, Libyan officials or ministers before Megrahi was freed.
The SNP sought to deflect criticism by supporting Cameron's demands for greater transparency by UK ministers. Angus Robertson, the SNP leader at Westminster, said Salmond had been furious the UK government had signed the PTA without his agreement, knowing it had no power to influence Scottish ministers or judges. "The SNP spoke out against Tony Blair's deal in the desert when it was first struck, but the UK denied that Megrahi was the target and refused to exclude him from the agreement," Robertson said.
"The UK government's negotiation of a prisoner transfer agreement and meetings between the UK government and Libya remain shrouded in secrecy. It is time for the UK to open up on Blair and Brown's dealings with Colonel Gaddafi."
Saif Gaddafi also tried to play down the controversy over last Thursday's celebrations at Tripoli airport, when Megrahi was greeted by him and a saltire-waving Libyan crowd. He insisted it was not an official celebration but a spontaneous display organised by Megrahi's large extended family and ordinary Libyans.
The Libyan government had planned to keep it low-key, but Megrahi's heavily televised release from Greenock prison and transfer to Glasgow airport had made his arrival home much more public.
"There was no official celebration, no guards of honour, no fireworks and no parade," he said. "We could have arranged a much better reception."
He denied speculation that Megrahi would be guest of honour at next week's 40th anniversary celebrations of his father's seizing power.
He added: "The decision by Scotland was not influenced by any of these things. I think the Scottish justice secretary is a great man. He made the right decision.
"So many of us think that, including so many of the relatives of the victims, because Mr Megrahi is innocent. One day, history will prove this."
Pressure grows on Gordon Brown over Libya trade talks
