Scotland's Justice Secretary is under pressure to explain claims he advised the man convicted of the Lockerbie bombing to drop his appeal against conviction to smooth the way for his compassionate release.
The allegation levelled against Kenny MacAskill – and denied by the Scottish Government – is contained in a new book, entitled Megrahi: You Are My Jury, in which Abdelbaset Ali Mohmed al Megrahi says he was "the innocent victim of dirty politics, a flawed investigation and judicial folly". It also makes claims about new evidence it says could have cleared the Libyan, but which the Crown Office failed to disclose to the defence.
Mr MacAskill is claimed to have made the offer to Megrahi through a Libyan official.
Scottish LibDem leader Willie Rennie called for Mr MacAskill and Lord Advocate Frank Mulholland to make a statement to Holyrood. He said: "Allegations of suppression of evidence and a Greenock Prison release deal between the Justice Secretary and Megrahi make it essential for a statement to be made to Parliament - it is important the Justice Secretary answers serious questions."
Tory leader Ruth Davidson said: "This is a staggering claim and implies the Scottish Justice Minister was offering legal advice to help a convicted killer escape prison."
Scottish Labour's justice spokesman, Lewis Macdonald, said Mr MacAskill may have "knowingly misled Parliament".
The new book details previously unseen evidence not disclosed to the defence, including forensics reports that suggest the fragment of circuit board found in the Lockerbie debris did not match those sold to the Libyans – as per the prosecution case at trial.
The book claims that the metal content did not match – but reports referring to this were not shared with the defence until 2009.
Megrahi dropped his appeal shortly before Mr MacAskill said he would be released on "compassionate grounds" on August 20, 2009. The book states that Mr MacAskill met Libyan officials, including Foreign Minister Abdulati al Obeidi, 10 days earlier.
Megrahi claimed: "After the meeting, the Libyan delegation came to the prison to visit me. Obeidi said that, towards the end of the meeting, MacAskill had asked to speak to him in private.
"Once the others had withdrawn, he stated that MacAskill gave him to understand that it would be easier to grant compassionate release if I dropped my appeal.
"He said he was not demanding that I do so, but the message seemed to me clear.
"I was legally entitled to continue the appeal, but I could not risk doing so."
Mr MacAskill has categorically denied the claim. A Scottish Government spokesman branded the book, as "third-hand hearsay".
The spokesman added: "These claims are wrong – and officials were present at all meetings the Justice Secretary had on this matter at all times. The minutes of this meeting and indeed all other meetings, including with Mr Megrahi in Greenock Prison, were published by the Scottish Government and have been in the public domain since September 2009.
"We can say categorically that neither did the Scottish Government have any involvement of any kind in Mr Megrahi dropping his appeal, or indeed any interest in it. That was entirely a matter for Mr Megrahi and his legal team."
The Crown Office said the decision was taken by Megrahi and his lawyers.
The book's author, John Ashton, who spent three years as a researcher with Megrahi's legal team, described the Crown's failure to disclose key information as a "scandal".
Professor Robert Black, one of the architects of the original trial, said the book appeared to have "put the final nail in the coffin of the conviction."
Prime Minister David Cameron described the book as "an insult to the families of the 270 people who were murdered".
[In today's edition of the Daily Express there is another report on this issue.]