Morsi supporters urge fight for Islam Islamist backers of Mohamed Morsi are resorting to religious rhetoric to galvanise support for the Egyptian president as the country's political stand-off showed little sign of resolution. Supporters and opponents of Mr Morsi held competing mass rallies in Cairo on Friday, as opposition anger deepened over the president's decision to strengthen his powers and rush through a new constitution. Pro-government clergy took over the pulpit at al Azhar mosque, the country's premier house of worship, and urged thousands of supporters of Mr Morsi to fight not for a president or a new constitution but for their religion. "Now is the battle for Islam," a Morsi supporter told thousands gathered at the mosque for the funeral for at least two members of the Muslim Brotherhood killed during street clashes with secular rivals this week. Egypt's two main social and political camps have been locked in a stand-off over Mr Morsi's attempt to increase his powers and push through a December 15 vote on a draft constitution decried as unbalanced by liberals, Christians and moderates. The crisis has reversed significant advances by the Egyptian stock market and slowed momentum towards securing international financing to shore up the country's cash reserves after a revolution last year that badly damaged its economy. Mr Morsi's vice-president, Mahmoud Mekki, said late on Friday that the president would be willing to postpone the referendum, provided he is not charged with violating the law. "The political forces who demand the delay of the referendum must provide guarantees that there will not be appeals in courts," he said. It was unclear whether the move would resolve Egypt's worst political crisis since Mr Morsi's election. Opposition leaders said they were studying and discussing it. Earlier in the day tens of thousands of Morsi opponents gathered in Cairo's Tahrir Square and near the presidential palace. "The people want the downfall of the regime," marchers chanted as they headed towards the palace, borrowing a slogan from last year's uprising against Hosni Mubarak. Some protesters broke through a barbed wire barricade around the palace, climbed on to army tanks and waved flags, Reuters news agency reported. Many said they would boycott the upcoming plebiscite. "I'm not going to vote," said Mariam Moheldin al-Masri, 28, a member of Mohamed ElBaradei's liberal Dostour party. Our strategy is we're going to continue doing what we're doing now: heading to the streets. State television reported clashes between supporters and opponents of Mr Morsi outside the al-Qaed Ibrahim mosque in Egypt's second city of Alexandria. Opponents of the president burnt down offices of the Muslim Brotherhood's Freedom and Justice party, including its headquarters in southeastern Cairo and a large office in the Cairo suburb of Maadi. Gihad Haddad, adviser to Mr Morsi, said on his Twitter page that dozens of offices affiliated with the Brotherhood and its political party had been attacked in recent days. Carrying the coffins of two Brotherhood members allegedly killed by opposition supporters during a chaotic street confrontation on Wednesday, Mr Morsi's supporters at al-Azhar called for revenge. Mohamed Hamed, a 64-year-old Brotherhood supporter who attended the funeral service, said: "They're attacking Islam and they're getting support from Europe and other foreign countries. We're praying for the people who were murdered by people sent by Baradei and [Hamdeen] Sabahi," a leftwing-nationalist opposition leader.