Pope Francis denounced "demagogic populism" on Friday and insisted that violence profanes God's name, in a wide-ranging speech as he visited Egypt to push for tolerance.
"Peace alone... is holy and no act of violence can be perpetrated in the name of God, for it would profane his name," the Catholic pontiff told a Muslim-Christian conference in Cairo.
Francis is in Egypt on a 27-hour visit to push for dialogue with Muslims and support the country's embattled Christian minority that has suffered a series of jihadist attacks.
In his speech, Francis said peace was not helped by "demagogic forms of populism... on the rise".
It is "essential", he added, to block "the flow of money and weapons destined to those who provoke violence".
Francis landed in Cairo earlier on Friday and met President Abdel Fattah al-Sisi and Ahmed al-Tayeb, the grand imam of the prestigious Islamic Al-Azhar institution.
He will later visit a church that was bombed in December.
That attack was followed by twin church bombings in April that killed 45 people, in the deadliest assault in recent memory on Egypt's Coptic Christian minority.
Security is extremely tight with the country under a state of emergency following the church bombings which were claimed by the Islamic State group.
On Saturday, the pontiff will preside over a mass for Egypt's small Catholic community, estimated to number around 272,000 people spread across various rites.