With Tripoli on the verge of collapse following key diplomatic and military gains, London and some U.S. lawmakers are refocusing on unsettled scores.
Lockerbie bomber and former Libyan intelligence officer Abdelbaset al-Megrahi was released from prison by Scottish officials in August 2009 on compassionate grounds because of a terminal prostate cancer diagnosis.
He is the only person convicted for the 1988 bombing of Pan Am Flight 103 in which 270 people were killed.
Scottish Justice Minister Kenny MacAskill maintains the decision to release Megrahi in 2009 was in line with policies set by prison and medical authorities, the Daily Telegraph newspaper in London reports. Megrahi, who was said to have about three months to live at the time of his release, is kept alive by a cancer drug not available in the United Kingdom, the report adds.
British Deputy Prime Minister Nick Clegg, however, said Megrahi committed one of the "most atrocious" acts of terror and should be "behind bars," the report adds.
Following the oil spill in the Gulf of Mexico last year, U.S. lawmakers started examining whether Megrahi's release was tied to a BP deal to look for oil in Libya. British, Scottish and BP officials deny the charges his release was related to oil.