Ban made the remarks in a statement issued by his spokesman on Saturday, a day after tens of thousands of people took to the streets across Egypt in response to a call by the Muslim Brotherhood for nationwide protests on the “Friday of Rage” against the army and its handpicked government.

The security forces and opponents of the Brotherhood fired on the supporters of ousted President Mohamed Morsi, leaving at least 173 people dead and some 1,330 more injured across Egypt.

On August 14, the military-appointed government launched a brutal crackdown on thousands of peaceful protesters in Cairo demanding the reinstatement of Morsi, leaving about 640 dead and hundreds of others injured.

The UN secretary general “strongly condemns attacks on churches, hospitals, and other public facilities, which he finds unacceptable," said Martin Nesirky, the spokesman for Ban.

"Whatever the grievances, there is no justification for destruction of infrastructure and property so important to Egypt's future," the spokesman added.

The UN chief said in the statement that preventing further loss of life in Egypt should be people’s "highest priority at this dangerous moment".

"He urges those in the street and those in authority to use maximum restraint and shift immediately to de-escalation,” the statement said.

"He appeals to the authorities and to the political leaders to adopt a credible plan to contain the violence and revive the political process hijacked by violence," it added.

Egypt has been experiencing unrelenting violence since July 3, when the army toppled Morsi, the first democratically elected Egyptian head of state, and suspended the constitution and dissolved the parliament. It also appointed the head of the Supreme Constitutional Court, Adly Mahmoud Mansour, as the new interim president.

The interim government in Egypt has been facing international condemnation over the killing of protesters. Amnesty International has called for a thorough and unbiased investigation into the August 14 massacre.

SHI/SHI