KENNY MacAskill has said he was taken back by the international interest in his decision to free Abdelbaset Al-Megrahi, the only man convicted of the Lockerbie bombing.

Speaking about his forthcoming book on Lockerbie, the former justice secretary said some involved in the whole affair “should hang their head in shame”.

Al-Megrahi was freed on compassionate grounds in 2009, after serving eight years in prison. The decision was met with fierce criticism in the United States.

MacAskill told Holyrood magazine that it was his “Andy Warhol moment”.

He said: “What I can say, without disclosing the full contents of the book, I knew we were a cog in a wheel, what I didn’t realise was how small a cog and how big a wheel.

“I think what comes out of this is that others should hang their head in shame and none of them are in Scotland.”

MacAskill did not expand, other than to defend his decision to write a book on the case.

He said: “I have to say I think this is my opportunity to tell people [what happened], there are a lot of things out there that people want to know and I think I am entitled to do that.

“That’s how I see it, I think this is a matter more of setting the record straight.”

Al-Megrahi was jailed in 2001 for the 1988 bombing of Pan Am Flight 103, which claimed 270 lives. He was suffering terminal prostate cancer and was released when he was supposed to have had just three months to live.

He lived for another three years and survived the civil war in Libya.

Senator Kirsten Gillibrand said seeing Al-Megrahi on Libyan state TV, was “another slap in the face” not just for the families of the victims but for all Americans.