A relative holds a picture of Jordanian pilot Muath al-Kasaesbeh, who was captured by Islamic State after his plane crashed in Syria
A relative holds a picture of Jordanian pilot Muath al-Kasaesbeh, who was burned alive by Islamic State after his plane crashed in Syria Reuters

The Sunni head of Cairo's al-Azhar Mosque, one of Egypt's most revered religious leaders, has called for the killing, crucifixion or mutilation of Islamic State (Isis) militants who burned a kidnapped Jordanian pilot alive.

Ahmed al-Tayeb, Grand Sheik of the mosque and the head of Sunni Islam's most respected seat of learning, said IS militants deserved the punishment because they were fighting God and his Prophet Mohammed.

A video published online by IS militants showed Jordanian pilot Moaz al-Kasasbeh burned alive. The footage shows a man standing in a cage engulfed in flames. The death of Kasasbeh was confirmed by Jordanian authorities.

A statement from Tayeb said that, by burning the pilot to death, the militants violated Islam's ban on the mutilation of bodies, even in wartime.

The pilot, 26, was captured by the Islamist militants in December, as his F-16 crashed near the IS stronghold of Raqqa, Syria.

Jordan executed female suicide bomber Sajida al-Rishawi following the release of the gruesome video.

Al-Rishawi, 44, was imprisoned in Jordan after attempting to detonate an explosives belt as part of the devastating 2005 hotel bombings in the capital city of Amman.

Jordan's state-run news agency said a senior al-Qaeda commander, who was convicted of plotting terror attacks in Jordan, has also been hanged.

Jordan had earlier vowed to give an "earth-shattering" response to the IS militants after it emerged that they had executed the pilot al-Kasasbeh.