Megrahi had been serving his life sentence at Greenock Prison
The release on compassionate grounds of the Libyan man convicted of the 1988 Lockerbie bombing has divided opinion on both sides of the Atlantic.
Abdelbaset Ali al-Megrahi, who was serving life in prison for murdering 270 people when Pan Am flight 103 exploded in 1988, was freed by Scottish Justice Secretary Kenny MacAskill because he has terminal prostate cancer.
BARACK OBAMA, US PRESIDENT
President Obama: ''We thought it was a mistake''
Mr Obama led the US in condemning the release of Lockerbie bomber Abdelbaset Ali al-Megrahi.
The president said: "We have been in contact with the Scottish Government indicating that we objected to this. We thought it was a mistake.
"We are now in contact with the Libyan government and want to make sure that if this transfer has taken place, that he is not welcomed back in some way but should instead be under house arrest."
FRANK DUGGAN, PRESIDENT OF VICTIMS OF PAN AM 103
Mr Duggan, president of a group which represents the families of American victims of the bombing, said: "My understanding is that the man [Megrahi] really is within three months of dying, which is one of the issues we wanted cleared up.
"At the same time, we have always maintained he should remain in prison in Scotland and die there if it comes to that."
KARA WEIPZ, SISTER OF VICTIM
Ms Weipz, from Mount Laurel, New Jersey, lost her student brother Rick, 20, in the atrocity, and condemned the decision to release Megrahi.
She said: "I don't know how you show compassion to someone who has shown no remorse for what he has done and as Mr MacAskill praised the justice system and the investigation and the trial, how do you then show this person compassion? It's just utterly despicable.
"I think he should have died in prison. Why should he be returned to Libya? That's not what we were promised. We were always told he would serve out his full sentence in Scotland."
DAVID CAMERON, CONSERVATIVE LEADER
Conservative leader David Cameron: ''I think this is a very bad decision''
The Tory leader said he believed the decision to release Megrahi was the result of "some completely nonsensical thinking".
"This man was convicted of murdering 270 people, he showed no compassion to them, they weren't allowed to go home and die with their relatives in their own bed and I think this is a very bad decision," he added.
IAIN GRAY, SCOTTISH LABOUR LEADER
Mr Gray said, if he was first minister of Scotland, Megrahi would not be going home.
"He was convicted of the worst terrorist atrocity in our history, the mass murder of 270 people," said Mr Gray.
"While one can have sympathy for the family of a gravely ill prisoner, on balance, our duty is to honour and respect the victims of Lockerbie and have compassion for them. The SNP's handling of this case has let down Scotland."
TAVISH SCOTT, SCOTTISH LIB DEM LEADER
Mr Scott said: "The real lesson of this shambles for the SNP is that government is about responsibility, not publicity. We've endured a simply dreadful two weeks as Kenny MacAskill dithered over this big decision while the SNP spin machine was in overdrive.
"I feel sorry for the victims' families who have been put through this charade. They are unlikely to hear the truth of the wheeling and dealing that has gone on. Many also would have wanted to see the Megrahi appeal run its course."
TAM DALYELL, FORMER LABOUR MP
Mr Dalyell, a former father of the House of Commons, has consistently claimed Megrahi is innocent.
He said: "Mr MacAskill, the Scottish justice minister, has arrived at the right decision on compassionate grounds.
"I do not accept his endorsement of the guilt of Mr Megrahi, whom I continue to believe had nothing whatsoever to do with the crime of Lockerbie."
RUSSELL BROWN, LABOUR MP FOR DUMFRIES
Mr Brown said seeing a saltire waved at Tripoli airport was "stomach churning" and condemned the Scottish Government for failing to seek adequate assurances that Megrahi would not receive a hero's welcome.
"I have never been ashamed to see my country's flag waved before, but to see it misused to celebrate mass murder is outrageous," he said.
"This man is convicted of murdering 270 people in my part of Scotland and that conviction stands."
REV IAN GALLOWAY, CHURCH OF SCOTLAND
Mr Galloway said the decision "sent a message to the world about what it is to be Scottish", and predicted it would be a "defining moment for all of us".
He said: "We are defined as a nation by how we treat those who have chosen to hurt us. Do we choose mercy even when they did not chose mercy?
"This was not about whether one man was guilty or innocent. Nor is it about whether he had a right to mercy but whether we as a nation, despite the continuing pain of many, are willing to be merciful.
"I understand the deep anger and grief that still grips the souls of the victims' families and I respect their views, but to them, I would say justice is not lost in acting in mercy.
"Instead our deepest humanity is expressed for the better. To choose mercy is the tough choice and today our nation met that challenge."
JIM SWIRE, FATHER OF VICTIM
Bereaved father Dr Jim Swire: ''It's time we knew who killed our loved ones''
Mr Swire's daughter Flora was killed in the bombing of Pan Am Flight 103. He has long believed Megrahi was not involved and said he was "delighted" the Libyan had been set free.
"I think the whole process was a political stitch up from start to finish, which is something that needs to be gotten to the bottom of. Iran's involvement has never been properly laid out," he said.
"'I'd be astonished, but delighted, if we ever get to the bottom of the political implications behind the bombing and who carried it out."
PAMELA DIX, SISTER OF VICTIM
Ms Dix, who lost her brother Peter in the atrocity, criticised the celebrations that greeted Megrahi's return to Libya.
She said: "I think a hero's welcome is entirely inappropriate in the circumstances.
"I know the man maintains his innocence but I think discretion would have been the right thing in these circumstances. But that was probably too much to expect.
"He has been released on compassionate grounds but he remains a convicted man."
SIR RICHARD DALTON, FORMER UK AMBASSADOR TO LIBYA
Sir Richard, British ambassador to Libya between 1999 and 2002, said he understood public anger about the release but said it was the right decision.
He said: "Appalling though the atrocity was that led to the deaths of 270 people, there are not good reasons why anybody convicted of that crime should be excepted from normal rules which apply for considering release on compassionate grounds.
"There is no doubt that Megrahi has been sent home to die."
Sir Richard denied the UK would gain commercially, in terms of oil or gas contracts, as a result of the decision.
He added that the UK's relationship with the US would not be damaged, having been maintained despite "diverging" interests on occasions in the past.
JASON McCUE, HUMAN RIGHTS LAWYER
Mr McCue represents the families of the 141 people killed by IRA action between 1983 and 1996, who claim Libya supplied Semtex explosives to republican terrorists.
He said: "The entente cordiale with Libya appears to be indifferent to the sensibilities and legal rights of the victims of Libyan Semtex and, more generally, their human rights.
"The intended beneficiary of all this is Anglo-Libyan trade. It is politically short-sighted of both governments and repugnant to the memories of the dead."
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