Amid mounting pressure on Britain to hold an independent inquiry into circumstances that led to the release of the lockerbie bomber from Scotland, media reports revealed that Abdelbaset al-Megrahi 'manipulated' his illness to win freedom.
It was claimed that the Libyan refused chemotherapy in a Scottish prison in an attempt to make his condition deteriorate and force his release, the Daily Mail reported on Saturday.
Four influential US senators have sought a probe into Megrahi's release from a Scottish prison last year.
In an open letter, senators Robert Menendez, Frank Lautenberg, Charles Schumer and Kirsten Gillibrand called for an inquiry.
They want details on Megrahi's diagnosis and communications between British Petroleum and the government. It has been alleged that BP lobbied for Megrahi's release to secure an oil drilling deal with Libya.
Al-Megrahi was believed to be terminally ill with prostate cancer when he was sent home to Libya on compassionate grounds Aug 20 last year.
But since his release, Megrahi has responded well to a similar treatment -- which is available on the National Health Service (NHS) -- and there are claims that he could live another seven years.
Dr Andrew Fraser, the Scottish doctor responsible for assessing Megrahi's health a year ago, had assured the government that the bomber was resistant to treatment -- assumed to mean that body was not responding.
But, in fact, Megrahi chose to refuse the treatment, ITV has claimed.
It is understood that Megrahi discussed the treatment with Scottish doctors but said he would only undergo it with support of his family, who were in Libya, the report said.
Notes of a meeting in July last year, which have been released by the Scottish government, report that doctors told Megrahi that he needed to 'take his medication regularly' -- suggesting that he was skipping doses that would have improved his health.
Just days later, his condition began to undergo such a dramatic deterioration that it appears to have been the deciding factor in his release.
Friday's disclosure raises questions over whether Megrahi made a calculated risk to refuse his medication so he would appear more frail just weeks before the decision to release him was made.
Megrahi, 58, the only person convicted of the 1988 bombing of Pan Am Flight 103 over Lockerbie town in Scotland that killed 270 people, was released from a life sentence after doctors said he had only three months to live.
Asked whether he had discussed Megrahi's refusal to be treated with Dr Fraser, Scottish first minister Alex Salmond said Friday, "It is not my job to raise issues with Dr Fraser. It was Dr Fraser's job to make the prognosis. It was then (Scottish justice secretary) Kenny MacAskill's job to act on any other information that he was receiving."
Dr Fraser declined to comment. The revelations came as Libya appeared to have caved in to Western demands not to celebrate the first anniversary of Megrahi's release.
Diplomats had warned Libya that a repeat of the festivities that marked his return would be deeply offensive to the families of the victims of the attack.
A Libyan official said only "quiet celebrations" would take place and that the country's leader Colonel Muammar Gaddafi did "not wish to cause offence in other parts of the world, especially Britain and America".