A sermon at the mosque where the Manchester bomber worshipped called for the support of armed jihadist fighters, according to two Muslim scholars.
An imam at Didsbury Mosque in December 2016 was recorded praying for "victory" for "our brothers and sisters right now in Aleppo and Syria and Iraq".
Scholars Usama Hasan and Shaykh Rehan said it referred to "military jihad".
The imam, Mustafa Graf, says his sermon did not call for armed jihad and he has never preached radical Islam.
The recording the BBC obtained is of Friday prayers at the mosque six months before Salman Abedi detonated a suicide bomb following an Ariana Grande concert at Manchester Arena in May 2017.