A Sunni group led by influential cleric Sheikh Yusuf al-Qaradawi has issued a fatwa urging Egyptians to ignore a call by their army chief to stage rallies in support of a crackdown on "terrorism".
The Association of Muslim Scholars issued the fatwa, or religious decree, late Wednesday "prohibiting (Egyptians from) responding to any call leading to civil war or covering up (the army's actions) of violence against any party, or inciting sedition".
Egypt's army chief General Abdel Fattah al-Sisi on Wednesday called for mass rallies on Friday to support a security force crackdown on "terrorism and violence".
With tensions already running high three weeks after the military ousted president Mohamed Morsi, Sisi's call for demonstrations raises the prospect of further deadly violence.
His call was denounced by Islamists in Egypt who branded it a call to "civil war" ahead of their own mass protests on Friday to demand Morsi's reinstatement.
Qaradawi's Doha-based Sunni association urged "all Egyptians -- people, parties, army and police -- to preserve their country's security and prevent all that could lead to a civil war in which all sides will be losers".
It said Egyptians should "use wisdom to overcome this crisis... preserve the peaceful nature of their protests, and to be patient under all conditions".
It also urged other countries to come up with "an urgent initiative to resolve this dangerous crisis that threatens the security of Egypt as well as the Arab and Muslim world".
Qaradawi, an Egyptian-born Qatari, is seen as a spiritual guide to the Muslim Brotherhood to which Morsi belongs. Earlier in July, he had issued a fatwa urging Egyptians to support the ousted leader.
The 86-year-old cleric is a regular commentator on Doha-based Al-Jazeera satellite television and has millions of supporters across the Arab world.