New documents obtained by Al-Jazeera claim to show Iranian militants were behind the 1988 attack that killed 270 people. Foreign Ministry spokeswoman Marzieh Afkham told AFP:
We reject any claims of Iranian involvement in this act of terror. Iran's stance not only on this case but on all terrorist-related issues is quite clear: Iran flatly denies (links) to any act of terror.
Scotland's Crown Office says there is 'nothing new' in the latest claims that Iran was responsible for the Lockerbie air disaster.
"Mesbahi's claim that Iran was responsible was first reported in the media in the late 1990s and was available to the defence before the trial but they did not call him as a witness.
"The only appropriate forum for the determination of guilt or innocence is the criminal court, and Mr Megrahi was convicted unanimously by three senior judges. His conviction was upheld unanimously by five judges, in an Appeal Court presided over by the Lord Justice General, Scotland’s most senior judge.
"As the investigation remains live, it would not be appropriate to offer further comment."
The Lockerbie bombing was ordered by Iran in retaliation for a US strike on an Iranian passenger plane, a new documentary has claimed.
Libyan Abdelbaset al-Megrahi was convicted of the bombing of Pan Am flight 103 over Scotland in which 270 people were killed more than 25 years ago.
But former Iranian intelligence officer Abolghassem Mesbahi has told an Al Jazeera documentary that the bombing was ordered by Tehran. He says it was carried out by the Syrian-based Popular Front for the Liberation of Palestine-General Command.
It's claimed it was in retaliation for a US navy strike on an Iranian commercial jet six months earlier, in which 290 people died.The US ship apparently mistook the plane for an F-14 fighter jet.
"Iran decided to retaliate as soon as possible. The decision was made by the whole system in Iran and confirmed by Ayatollah Khomeini.
The target of the Iranian decision makers was to copy exactly what's happened to the Iranian Airbus. Everything exactly same, minimum 290 people dead. This was the target of the Iranian decision makers."
– Abolghassem Mesbahi, former Iranian Intelligence Officer