Prosecutors are said to be closing in on two Libyans suspected of being involved in the Lockerbie bombing.
The Times reports US and Scottish investigators are hopeful they will get permission to interview Abdullah al-Senussi – believed to have been behind the atrocity – and Abu Agila Mas’ud, the bomb maker.
Both men are held in a Libyan prison.
It comes after Fayez al-Sarraj, the country’s UN-backed prime minister, said his government is willing to extradite Hashem Abedi, wanted for questioning in Britain after the attack at an Ariana Grande concert in Manchester in which 22 people were killed.
Hashem’s brother, Salman Ramadan Abedi, was the suicide bomber who carried out the Manchester attack.
The assurances have given police involved in the Lockerbie investigation encouragement, according to the newspaper.
It said officers described Libya’s response to diplomatic approaches as “positive and constructive”.
Abdul Baset Ali al-Megrahi was the one person convicted for the bombing. He died in May 2012.