Thousands supporters of former President Mohammed Morsi and his Muslim Brotherhood marched through the streets of Cairo after leaving mosques where they had attended Friday prayers.

They later assembled at a number of locations, calling for the reinstatement of what they described as Egypt's democratically elected president and government, which was ousted by the military a month ago. 

Instead of abandoning already existing protest camps, as demanded by the civilian government that the military has installed, Morsi's supporters defied the order, by starting a sit-in at at least one new location, near Cairo's international airport.

The AFP news agency also reported that police had used tear gas to try to break up a new protest camp outside a compound where television stations are located.

On the diplomatic front, meanwhile, US Under Secretary William Burns arrived in the Egyptian capital on Friday, in a bid to convince Morsi's supporters and the military-installed interim government to resolve their differences through dialogue.

Burns' arrival in Cairo comes on the heels of trips to the country earlier this week by German Foreign Minister Guido Westerwelle and the European Union's foreign policy coordinator, Catherine Ashton. 

It also comes a day after US Secretary of State John Kerry angered Morsi's supporters by appearing to express support for the military takeover.

"The military was asked to intervene by millions and millions of people, all of whom were afraid of a descendance into chaos, into violence," Kerry told the Pakistani broadcaster Geo on Thursday.             

"And the military did not take over, to the best of our judgement - so far. To run the country, there's a civilian government. In effect, they were restoring democracy."

A spokesman for Morsi's Muslim Brotherhood denounced Kerry's comments, accusing the US of being "complicit" in what the US has refused to call a military coup.

The July 3 removal of Morsi's government has further deepened a split in the country, with the deaths of than 200 people, mostly Muslim Brotherhood supporters, in street clashes since then.

pfd/jr (dpa, Reuters, AFP, AP)