Army chief Abdel Fattah al-Sisi met overnight with Islamist leaders to try and resolve the crisis pitting supporters of ousted president Mohammed Morsi against Egypt's new leaders.

Sisi "met with several representatives of the Islamist movements ... and stressed that there are opportunities for a peaceful solution to the crisis provided all sides reject violence," army spokesman Colonel Ahmed Aly said in a statement, without specifying who his interlocutors were.

Egypt's army chief General Abdel Fattah al-Sisi has lashed out at the United States, urging Washington to do more to pressure the Muslim Brotherhood to end its rallies.

In a rare interview with the Washington Post, the commander -- who led the military coup that ousted Islamist president Mohamed Morsi one month ago -- warned of police action to disperse such protests.

U.S. Defense Secretary Chuck Hagel on Saturday urged his Egyptian counterpart to support an "inclusive" political process in the wake of the ouster of Islamist president Mohammed Morsi.

Hagel spoke early Saturday with General Abdel Fattah al-Sisi, the head of Egypt's armed forces, which drove Morsi from power on July 3 amid massive protests against his year-long rule.

Egypt's interior ministry Saturday repeated its call for supporters of ousted Islamist president Mohammed Morsi to end their sit-ins, saying that would allow the Muslim Brotherhood to return to politics.

The ministry, in a televised statement, called on protesters in Cairo's Rabaa al-Adawiya and Nahda squares to return to their homes and work.

U.S. Secretary of State John Kerry appeared to try to distance himself Friday from comments he made that were seen as endorsing the Egyptian military's overthrow of a civilian ruler.

Washington has struggled to articulate a coherent position on the situation in Egypt, where the army stepped in to depose president Mohammed Morsi following large-scale street protests.

Al-Qaida chief Ayman al-Zawahiri accused the U.S. of "plotting" with Egypt's military, secularists and Christians to overthrow Islamist president Mohammed Morsi, in an audio recording posted on militant Islamist forums.

In his first public comment on the July 3 military coup, the al-Qaida boss, himself an Egyptian, said: "Crusaders and secularists and the Americanized army have converged ... with Gulf money and American plotting to topple Mohamed Morsi's government."

Rights group Amnesty International on Friday called for an immediate investigation into allegations that supporters of ousted Egyptian president Mohammed Morsi tortured opponents in Cairo.

"Evidence, including testimonies from survivors, indicates that supporters of deposed President Mohammed Morsi tortured individuals from a rival political camp," the group said in a statement.

US Middle East envoy William Burns arrived in Cairo on Friday night, a senior Egyptian official said, as international efforts to resolve Egypt's political crisis ramp up.

Burns, the under secretary of state for the Middle East, has already visited Egypt once since the July 3 ouster of president Mohammed Morsi.

Egypt's interim vice president Mohammed ElBaradei has called for a halt to violence followed by talks with the Muslim Brotherhood and other backers of ousted president Mohammed Morsi.

His comments, in an interview with the Washington Post, were published Friday as Morsi supporters staged fresh rallies in Egypt in defiance of government orders that their protest camps be broken up.

U.S. Secretary of State John Kerry and his counterpart from the United Arab Emirates called on Friday for Egypt to return to normal and restore stability after fresh protests.

"Egypt needs to get back to a new normal," Kerry said on a stopover in London, after Islamist backers of Egypt's deposed president Mohammed Morsi staged defiant rallies.