Sheik Ahmed el-Tayeb, the grand imam of the Al-Azhar mosque, said in a statement that "peaceful opposition to the legitimate leader is religiously permissible and accepted."
Cairo's Al-Azhar is the Sunni Muslim world's foremost seat of learning. The views of its imam are taken seriously and widely interpreted to be the moderate voice of Islam.
Mursi's opponents are planning mass protests on June 30 calling on him to step down a year after he narrowly won the presidency in a run-off against the last prime minister to serve under his ousted predecessor Hosni Mubarak.
El-Tayeb's statement, posted on Al-Azhar's official website, came one day after he and the patriarch of Egypt's Coptic Christians, Pope Tawadros II, met Mursi. The timing of the meeting suggested that Morsi wanted the public backing of the two religious leaders ahead of the June 30 protests. An official statement issued by Mursi's office appeared to back this interpretation.
More From This Section
Mursi, it said, "expressed his appreciation ... To how they can contribute to bolstering national unity and maintaining the nation's supreme interests, along with safeguarding the nation's security and stability." The meeting also dealt with "current conditions and challenges facing the nation," the statement said.
Relations between Tawadros and Mursi have not been smooth. The pope accused Morsi of doing nothing when his patriarchal seat, the Cathedral of St. Mark in Cairo, came under attack by rocks and firebombs in April, while security forces looked on.
Today's statement by el-Tayeb pointed to the gap between the cleric and Mursi's allies at a time when much of the country is seething with anger and frustration over the perceived failure of the Egyptian leader to effectively tackle any of the country's pressing problems, including surging crime, high unemployment, electricity outages, fuel shortages and rising prices.