US President Barack Obama on Saturday urged Egypt's opposition parties and President Mohamed Morsi to renounce violence and engage in a constructive dialogue.
"Obviously we are all looking at the situation with concern," Obama told a news conference in South Africa, commenting on clashes in Egypt which killed two people, including an American student.
He called on the parties involved to avoid violence, saying instability in Egypt could spill over into the surrounding region.
Egypt is expecting mass rallies on Sunday against President Morsi and the Muslim Brotherhood from which he hails. President Morsi supporters are already gathered at the Rabaa Al-Adawiya Square in Cairo's Nasr City located only few kilometres away from the presidential palace where opposition demonstrations are planning to converge.