The head of the jihadist group chose the first Friday prayer service of Ramadan to make an audacious display of power in the city that the Sunni Islamists have now controlled for three weeks.

Speaking from the balcony of the mosque, al-Baghdadi urged the world’s Muslims to flock to the Islamic caliphate across Syria and Iraq declared by his organisation last week.

Under his direction, the Islamic world would be returned to “dignity, might, rights and leadership”, announced the self-anointed “Caliph Ibrahim”.

“I am the wali (leader) who presides over you, though I am not the best of you, so if you see that I am right, assist me,” he said, dressed in a black turban and robe.