The Scottish government is considering whether the man convicted of the Lockerbie bombing should be set free.

Ministers are examining the possibility of giving Abdelbaset Ali Mohmed al-Megrahi early release on compassionate grounds instead of a prisoner transfer requested by the Libyan government last week.

Under the transfer deal, brokered by London and Tripoli, prisoners cannot leave the country while criminal proceedings are ongoing.

Megrahi, 57, who is terminally ill with prostate cancer, would have to abandon an appeal against his conviction if his application for release were to be granted.

According to senior government sources, Kenny Mac-Askill, the Scottish justice secretary, believes an alternative would be to allow him to leave on humanitarian grounds while allowing his appeal to continue, if necessary by his family after he dies.

Such a move would be opposed by the Conservatives and Liberal Democrats, who believe he should serve his full life sentence in Scotland.

Megrahi was convicted of the 1988 atrocity in which 270 people died by a Scottish court in the Netherlands. His first appeal failed but last year the Scottish Criminal Cases Re-view Commission referred the case back to the Appeal Court for further consideration.

Alex Salmond is believed to harbour doubts about the strength of the case against Megrahi. Last week the first minister said he wanted to see the prisoner face “due process” through the Scottish courts.

A source close to Salmond said that could involve releasing him “on licence” under the supervision of the Libyan authorities.

The proposal was welcomed by Jim Swire, whose daughter Flora died in the crash and who has since pursued a tireless quest for information about the bombing.

“This is a genuine alternative for him. The dropping of an appeal would be a disaster for those who seek the truth. We want to see evidence old and new exposed in court,” he said.

“Megrahi bitterly misses his family and it would be the best of both worlds if he could be reunited with them while continuing with his appeal.”

Robert Black, the Edinburgh law professor who helped to broker Megrahi’s original trial, said: “In my view, that’s the ideal solution.

“The problem up until now is that compassionate release is not granted unless the individual has three months or less to live and cancer specialists are very wary of getting it wrong. I understand that his condition has rapidly deteriorated, so a specialist may well now be of the opinion that he is ill enough to be released.”

However, Bill Aitken, justice spokesman for the Scottish Conservatives, warned against giving Megrahi special treatment.

“There has to be a presumption that Megrahi will finish his sentence in Scotland unless it can be proved that there are compelling reasons why not,” he said. “His case must not be handled any differently from anyone else in similar circumstances and there would be great resentment if this was to be the case.

“While there is a very voluble, eloquent and no doubt sincere minority of people who want him released, many of the relatives of the deceased wish him to spend the rest of his life in jail and they are not receiving the same attention.”

Bob Monetti, whose son Rick was among the victims of the bombing, said releasing Megrahi would be an “act of betrayal” by the Scottish government.

“The deal that the Scottish and US authorities agreed was that he would serve out his term in Scotland. He is right where he belongs.

“If they release him back to Libya, that’s a bad joke. The families would feel immensely betrayed. There will be a lot of anger.”

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