But the speculation about the role played by London has been fuelled by the disclosure that Business Secretary Peter Mandelson met Seif al-Islam this month during a holiday on the Greek island of Corfu.
Mandelson confirmed Saturday that Islam had raised the issue of Megrahi. But he said the issue of his release was "entirely a decision for the Scottish justice minister, that's how it was left, that's how it was well understood."
Now that the decision had been made it was not London's role to "second guess" it, he added.
Rosemary Hollis, a Middle East specialist from City University in London, said Kadhafi senior clearly thought Britain was behind the decision.
"Colonel Kadhafi himself said thank you to Queen Elizabeth and Gordon Brown. How is he supposed to understand that the Scottish system was entirely in charge of what happened? It is a little difficult to believe," she told Sky News.