The European Union's foreign policy chief was scheduled to hold crisis talks in Cairo on Monday after the weekend killing of at least 72 supporters of Egypt's deposed Islamist president plunged the pivotal Arab country deeper into turmoil.
Underscoring the risk of more bloodshed, several thousand supporters of ousted President Mohamed Mursi's Muslim Brotherhood threatened to march on the military's intelligence headquarters in defiance of a warning from the army to stay away.
They turned back early Monday, having left the site of a Brotherhood vigil in northern Cairo chanting, "Our blood and souls we sacrifice for Mursi."
The dawn killings on Saturday, following a day of rival mass rallies, deepened the turmoil plaguing the country since the army shunted Egypt's first freely elected president from power on July 3.
The West is increasingly concerned about the risk of broader conflict in the Arab world's most populous country, a bridge between the Middle East and Africa and recipient of more than $1 billion in military aid from the United States.
Catherine Ashton, the EU's foreign policy chief, was scheduled to meet General Abdel Fattah al-Sisi, the head of the Egyptian armed forces who led the overthrow of Mursi, the country's interim president, Adli Mansour, and officials of the Freedom and Justice Party, the Brotherhood's political wing.
Ashton, in a statement, said she would press for a "fully inclusive transition process, taking in all political groups, including the Muslim Brotherhood."
Thousands of Brotherhood supporters have been staging a weeks-long vigil outside the Rabaa al-Adawiya mosque in northern Cairo to demand Mursi's reinstatement, defying threats by Egypt's army-installed authorities to disperse them.
'EGYPT'S DEVOTED SON'
Sisi, who was appointed by Mursi only to turn against him after a year into the president's rule, made his first appearance since the killings, smiling before television cameras at a graduation ceremony for police recruits dressed in starched white uniforms on Sunday.
He received a standing ovation and was hailed by Interior Minister Mohamed Ibrahim as "Egypt's devoted son."
Fawning coverage in state and private media reflected Sisi's rising political star in a country ruled by former military officers for six decades before a 2011 popular uprising toppled veteran autocrat Hosni Mubarak.
The military says it does not want to retain power and aims to hand over to full civilian rule with a "road map" to parliamentary elections in about six months.
But the very public role of Sisi as face of the new order has sown doubt in the army's intentions, and the Brotherhood says it wants nothing to do with his road map.
Mursi has been in army detention since he was ousted and the military-backed interim government has placed him under investigation on charges that include murder.
Speaking to Reuters on Sunday, interim Foreign Minister Nabil Fahmy said deepening divisions would lead to "more tragedies." He blamed the Brotherhood for the violence, but said they should be part of the country's political future.
"If they decide to withdraw from politics, it will be disappointing. If they decide to pursue violence, then you are looking at a completely different confrontation," Fahmy said.
"Even if I personally reject their positions or ideology, they have to find their place in Egypt's political life."