In a statement, the President of the European Council Herman Van Rompuy and the President of the European Commission Jose Manuel Barroso called on all sides in Egypt to show restraint and prevent further escalation of the violence.
"To this effect, together with its member states, the EU will urgently review in the coming days its relations with Egypt and adopt measures aimed at pursuing these goals," the statement said.
Supporters of ousted president Mohammed Morsi were planning fresh protests across Cairo on Sunday, raising fears of further bloodshed after hundreds were killed this week.
However, according to Al Jazeera, the group announced Sunday afternoon that it was canceling protests in Cairo due to safety concerns. Citing Muslim Brotherhood officials, the report said snipers were situated on buildings and along the planned routes.
Mohammed ElBaradei, who served recently as Egypt's interim vice president until resigning Thursday following the violence left Cairo for Austria.
In defiance of the military-backed government's crackdown, Morsi's Muslim Brotherhood group and its Islamist allies announced they will hold at least nine marches across the Egyptian capital, and gather neat the Constitutional Court in southern Cairo.
More than 700 people have died, most of them backers of Morsi, in four days of violence. That has earned Egypt stiff condemnation from Western nations, uncomfortable with Islamist rule but also with the overthrow of an elected government.
The crackdown has, however, drawn messages of support from key Arab allies like Saudi Arabia, which have long feared the spread of Brotherhood ideology to the Gulf monarchies.
Blaming a defiant Brotherhood for the bloodshed, Egyptian Prime Minister Hazem el-Beblawi proposed dissolving the group in a move that would force it underground and could usher in mass arrests of its members countrywide.
The government said it was studying the possibility.
Egypt's military leader, Gen. Abdel-Fatah el-Sissi, said Sunday that the army has no intention to seize power, while calling on Islamists to join the political process.
El-Sissi, who led the July 3 coup that ousted Morsi, made the comments during his first appearance since a deadly crackdown Wednesday on two encampments of Morsi supporters. He appeared at a gathering of top military commanders and police chiefs, where he vowed the army will not stand by silently in the face of violence.
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