The United States on Friday called on Egypt's military to free deposed president Mohamed Morsi, as tens of thousands of his supporters vowed to keep fighting for his reinstatement.
State Department spokeswoman Jen Psaki said the United States agreed with Germany's earlier appeal for Morsi to be released and was "publicly" making the same request.
Morsi has been held in a "safe place," according to Egypt's interim leaders, and has not been seen in public since his ouster on July 3.
Psaki said US officials had been in regular contact with all sectors of Egyptian society, and Washington was echoing German calls for "an end to restrictions on Mr Morsi's whereabouts".
A German ministry spokesman said a "trusted institution" such as the International Committee of the Red Cross should be granted access to Morsi.
As night fell on Cairo, tens of thousands of Islamist protesters prayed and broke their fast together on the first weekend of the holy month of Ramadan.
They had spent the day protesting outside the Rabaa al-Adawiya mosque in the Nasr city neighbourhood, holding Egyptian flags and Korans, chanting against the military coup that unseated Egypt's first freely elected president.
"We are here to deliver a message to the military that we won't give up on legitimacy. We will fight for our rights," said protester Ashraf Fangari.
"We are here to defend our votes. They were stolen from us."
Millions of Egyptians had taken to the streets to demand Morsi's resignation -- accusing him of being a puppet of the Muslim Brotherhood and of failing to fulfil the people's aspirations of freedom and social justice.
The mass anti-Morsi demonstrations prompted an army intervention and days of bloody clashes.
"We will continue to resist. We will stay one or two months, or even one or two years. We won't leave here until our president, Mohamed Morsi, comes back," influential Islamist leader Safwat Hegazi told Friday's crowd.
Hegazi demanded Morsi's reinstatement, immediate parliamentary elections and a committee to oversee a plan for national reconciliation.
Thousands also massed in support of the ousted president outside the University of Cairo, watched over by a heavy security presence.
Despite the defiance, the interim authorities are pressing ahead with forming a new government amid help from Gulf states to shore up the faltering economy.
Hazem al-Beblawi, who was appointed premier on Tuesday, is expected to finalise the makeup of the interim government by the middle of next week, cabinet sources told the official MENA news agency.
The Muslim Brotherhood, the Islamist group from which Morsi emerged, is now in tatters, its leadership detained, on the run or keeping a low profile following Morsi's overthrow.
The onset of holy month of Ramadan, usually a time of communal sharing and unity, has been marked by tensions after deadly clashes.
Rival demonstrators also rallied in the capital on Friday.
In Cairo's Tahrir Square and outside the Ittihadiya presidential palace, hundreds of anti-Morsi protesters sat down for a festive iftar.
The rallies have raised fears of more of the violence that has shaken Egypt since the army removed Morsi.
In the worst single incident, clashes at an army building in Cairo on Monday killed 53 people, mostly Morsi supporters.
The Brotherhood accuses the army of "massacring" its supporters, while the army says soldiers were attacked by "terrorists" and armed protesters.
On Friday, gunmen in the Suez Canal city of Ismailia killed a police conscript and wounded an officer when they tried to stop a vehicle the armed group was travelling in, MENA reported on Friday.
The gunmen escaped, but security forces were tracking them down, Ismailiya police chief General Mohamed Eid told MENA.
The restive Sinai peninsula, home to Egypt's luxury Red Sea resorts, has been hit by a surge of violence, with militants killing a police officer early on Friday, officials said.
A Coptic Christian man was found decapitated on Thursday five days after being kidnapped, and on Wednesday, two people died in an attack on a checkpoint in the Sinai.
Police are hunting Brotherhood chief Mohammed Badie and other senior leaders suspected of inciting violence, after arrest warrants were issued on Wednesday.
The public prosecutor has pressed charges against 200 of 650 people detained during Monday's violence.
A US State Department spokeswoman said the arrests were "not in line with the national reconciliation" the interim government and military say they want.
Adly Mansour, the military-appointed caretaker president, has set a timetable for elections by early next year.
But Morsi opponents and supporters alike have criticised the interim charter he issued on Monday to replace the Islamist-drafted constitution and steer a transition that the army itself has acknowledged will be "difficult".
Many fear a repetition of the mistakes of the last military-led transition, between Hosni Mubarak's ouster in 2011 and Morsi's election in June 2012.