Western leaders struggle for response to violence in Egypt An Egyptian walks among the burned remains of the Rabaah al-Adawiya mosque The US cancelled joint exercises with Egypt's military on Thursday but stopped short of suspending aid to Cairo as western leaders grappled with how best to respond to a bloody crackdown on Islamists. At least 638 people were killed in clashes between security forces and Muslim Brotherhood supporters in Cairo and elsewhere, according to official figures released on Thursday. The rising toll meant that Wednesday's raid by authorities on Brotherhood protest camps set up after a July 3 coup that ousted former President Mohamed Morsi had resulted in the deadliest day seen in Egypt since the 2011 uprising that led to the overthrow of former president Hosni Mubarak. The Muslim Brotherhood has called for a nationwide protest on Friday. The UN Security Council held an emergency meeting on Thursday evening to discuss the situation in Egypt. Diplomats said the council was unlikely to issue a statement after the meeting. Chuck Hagel, the US defence secretary, spoke with army chief Gen Abdel Fattah al-Sision on Thursday. In a statement following the call, he said he had "made it clear that the violence and inadequate steps towards reconciliation are putting important elements of our longstanding defence co-operation at risk." In a statement that appeared to be a prelude to a formal ban of the group, the military-backed government accused "elements" of the Brotherhood of carrying out "terrorist acts" that it said came "within the framework of a criminal plot clearly aimed at undermining the cornerstones of the Egyptian state." For their part, the Islamist movement's leaders, who have denied inciting any violence, insisted on Thursday that they remained committed to peaceful protests and determined to regain the power they lost with Mr Morsi's removal. We will always be non-violent and peaceful. We remain strong, defiant and resolved," Gehad El-Haddad, a spokesman for the Brotherhood, wrote on Twitter. We will push forward until we bring down this military coup. While the streets of Cairo were largely calm, the stand-off between the two sides continued to be felt elsewhere in Egypt and in an economy that had been on the verge of collapse and dependent on funding from Gulf allies before the latest violence. Foreign companies including Toyota, GM, Royal Dutch Shell and Electrolux said they had shut factories and closed offices in Egypt in response to the latest violence. The crackdown on the Islamist protest camps has also triggered a wave of attacks against dozens of Christian targets, including churches, schools and businesses owned by Coptic Christians. Father Ayoub Youssef, a Catholic priest in the village of Delga in Minya in southern Egypt, told the Financial Times that attackers who had looted and set alight an ancient 1400-year-old church on Wednesday had returned on Thursday to demolish its remains. "No one is stopping them," he said. There is no army and no police. They have brought tools and are removing the marble and the ancient pictures. We have contacted everyone you can imagine. In his first public response to Wednesday's events in Cairo, President Barack Obama condemned the use of violence by Egyptian authorities. The US still believed that engagement could "support a transition back to a democratically elected civilian government," he said, but added that Washington's co-operation could not continue as usual when civilians were being killed. He announced the suspension of the Bright Star joint military exercise, which is held every two years and was due to take place this year. But the president made no mention of the broader $1.5bn in aid that the US gives to Egypt each year. The Egyptian presidency responded to Mr Obama's comments about the recent violence, saying that they were not based on "facts" and that Egypt was facing "terrorist acts." François Hollande, the French president, demanded "an immediate stop to the repression" and said "everything must be done to avoid civil war." He added that France was committed to finding a political solution, and called for elections to be organised as soon as possible. Turkey called on the UN Security Council to meet urgently to discuss the bloodshed in Egypt. Those who remain silent in the face of this massacre are as guilty as those who carried it out. The UN Security Council must convene quickly," Recep Tayyip Erdogan, the Turkish prime minister, told a news conference. "If the west does not act sincerely, democracy will be questioned throughout the world," he said, adding that those responsible for this week's "massacre" should stand trial. Denmark announced on Thursday that it was suspending all aid to Egypt. "The Arab spring ended yesterday in an Egyptian tragedy," the country's development minister, Christian Friis Bach, said on Twitter. The condemnation was not unanimous. The United Arab Emirates on Thursday praised the Egyptian government's "maximum self-control." Additional reporting by Richard Milne in Stockholm, Adam Thomson in Paris and Daniel Dombey in Istanbul