Abdelbaset Ali Mohmed al-Megrahi, the former Libyan intelligence agent, 56, is serving a life sentence with a minimum term of 27 years for the 1988 bombing of Pan Am flight 103. This plan crash took lives of 270 people, including all 259 passengers on board and 11 residents of Lockerbie, the Scottish town, where the plane crashed. He was convicted in 2001 since than he is fighting a legal battle to overturn the guilty verdict.

He has been diagnosed with prostate cancer after hospital tests last month. Solicitor Tony Kelly revealed that the disease had spread to other parts of his body. He added that it would be "unwise" to attempt to predict his client's life expectancy but stressed that "the fight to overturn his wrongful conviction" would continue.

Megrahi lost an appeal in 2002, but was given a fresh chance to clear his name in June last year when the Scottish Criminal Cases Review Commission (SCCRC) referred his case back to appeal judges for a second time.

Last week, Megrahi won a legal victory when judges ruled his appeal could have a wide-ranging focus.

Dr Swire, who is also spokesman for the UK Families Flight 103 group, added: "If his prognosis is bad then I hope that the Scottish authorities would look for a way of speeding up the next appeal without compromising the fairness of it.

"It would be an act of great humanity to do that."