LONDON (AP) — The regrets of a cancer expert who assessed the only man ever convicted of the 1988 Lockerbie jetliner bombing have intensified the anger felt by victims' relatives over Scotland's decision to release the Libyan on compassionate grounds.

Professor Karol Sikora and other experts had said Abdel Baset al-Megrahi probably had only three months to live when he was freed from a Scottish jail last August and allowed to return home to Libya. But one year later, Al-Megrahi, who is being treated for prostate cancer, is still alive.

Sikora, one of three experts who assessed al-Megrahi's health for Libyan authorities, was quoted by Britain's Observer newspaper Sunday as saying he should have been more cautious about the chances of survival.

"If I could go back in time, I would have probably been more vague and tried to emphasize the statistical chances and not hard fact," Sikora was quoted as saying.

"In medicine we say 'Never say never and never say always,' because funny things happen. All you can do is give a statistical opinion," said Sikora, dean of the School of Medicine at Buckingham University, in central England.

Scottish authorities deny that the opinions of Sikora and the other experts who advised Libya entered into the decision to release al-Megrahi, though families contend that the advice must have played a role.

"It's obvious the whole thing was flawed," said Frank Duggan, president of the Victims of Pan Am Flight 103, an advocacy group that represents some of the families of those killed.

Duggan said Scottish Justice Secretary Kenny MacAskill had rejected a U.S. government request to commission an independent medical examination of al-Megrahi, and also has declined demands from families to publish in full the advice Scotland received from consultants.

"The Scottish government should be embarrassed and the U.K. government should be embarrassed," said Duggan, a retired lawyer from Rehoboth, Del., who advises some bereaved families. "It's no surprise to us that these doubts are coming out."

Al-Megrahi is the only person to have been jailed for the 1988 bombing of Pan Am Flight 103 above the small Scottish town of Lockerbie, which killed 259 people — mostly Americans — onboard and 11 on the ground.

He was convicted in 2001 and sentenced to serve at least 27 years in a Scottish prison, but released in August 2009 on compassionate grounds.

A report made public by Scottish authorities shows the Scottish Prison Service's medical chief, Andrew Fraser, was advised by four specialists at the time of al-Megrahi's release. The report described the three-month prognosis for al-Megrahi as "reasonable," but confirmed that none of those consulted ruled out that al-Megrahi might live longer.

Sikora said he was not taking responsibility for al-Megrahi's release. "No one asked me, 'Should we let him out?' All they said was, 'When do you think he will die?'" he was quoted as saying.

Rev. John Mosey, from Worcestershire, England, whose daughter Helga, 19, died in the bombing, said it was wrong to criticize those who had assessed al-Megrahi.

"The doctors in the case have been dragged through the mud, when really it is very difficult to assess how long someone will survive," he said. "It was a difficult decision to make and was made in good faith."

Susan Cohen, of Cape May Court House, N.J., whose 20-year-old daughter, Theodora, died in the attack, said Sikora's comments were the latest insult to the victims' loved ones.

"This is an added kick in the face and another example of them throwing rocks in the face of the families," Cohen said Sunday. "This whole thing is about business interests, money and making profits," she said, referring to allegations that oil giant BP pressured Scotland to free al-Megrahi so it could win access to Libyan oil reserves.

MacAskill has denied BP had any role in the release of al-Megrahi. Former BP chief executive John Browne, who stepped down in 2007, said Saturday he held two meetings with Libyan leader Moammar Gadhafi but never discussed the release of prisoners.

BP has acknowledged that it lobbied the U.K. government as Britain and Libya were negotiating a prisoner transfer agreement — known as a PTA — in autumn 2007, but said it had not raised al-Megrahi's case. Al-Megrahi was not released under the deal, as he was freed on compassionate grounds rather than transferred to serve out his sentence.

"The PTA happened after I left the company. I went to see Col. Gadhafi twice and I think I moved things forward, but there was no discussion about the PTA and no agreement for exploration made at that time," Browne said, speaking Saturday at the Edinburgh International Book Festival.

Last week, four Democratic U.S. senators — Kirsten Gillibrand and Chuck Schumer of New York and Bob Menendez and Frank Lautenberg of New Jersey — sent a letter to Scottish First Minister Alex Salmond asking that al-Megrahi's full medical records be disclosed.

"We've never seen that medical evidence. We now know from the prison doctor that the cancer experts were not absolute in their view that al-Megrahi only had three months to live, so there is a lot of confusion here," Annabel Goldie, a Conservative Party lawmaker in Scotland's Parliament, said Sunday.

Duggan said Scottish authorities have repeatedly cited patients' confidentiality as their reason for not disclosing the records.

Sikora told the Observer he remains certain al-Megrahi will die of cancer, "I suspect in the next few weeks. To tell the truth, I'll be quite glad because we can move on."


Associated Press Writers Ben McConville in Edinburgh, Scotland, and Bruce Shipkowski, in Trenton, N.J., contributed to this report.