Cairo - Egypt's military chief called on Wednesday for mass demonstrations to give the army a mandate to deal with "violence and terrorism," signalling a possible crackdown against the Muslim Brotherhood and its supporters.
"I ask honourable Egyptians to take to the streets on Friday to give us a mandate to face potential violence and terrorism," Abdel-Fatah al-Sissi, who toppled Islamist president Mohammed Morsi, told a televised ceremony at a military college in Cairo.
"I want Egyptians to show the world that they have a willpower and decision-making. If some people resort to violence and terrorism, the army and police will be mandated to face this."
A senior official in the Brotherhood, to which Morsi belongs, dismissed al-Sissi's call.
"The millions will actually turn out on Friday but to support legitimacy and reject the coup," Essam al-Erian wrote on Facebook. "Al-Sissi's threats will serve him no good."
The anti-Islamist group Tamarod, which spearheaded the street protests that preceded Morsi's removal, backed al-Sissi's call.
The movement called on Egyptians to pack the nation's major squares on Friday to "support the Armed Forces' coming war on terrorism."
The Brotherhood has said it will hold rival rallies, raising the risk of clashes.
Both sides have traded blame for violence in which dozens of Egyptians have been killed since Morsi's overthrow by the army on 3 July, after unprecedented protests by millions to demand the Islamist president step down.
The Brotherhood has condemned Morsi's toppling as a coup and vowed to protest until he is restored to office.
Nobel Peace Prize laureate Mohammed ElBaradei, a vice president in the military-backed interim government, urged compromise, addressing a first session of reconciliation talks proposed by caretaker President Adli Mansour, attended by secular politicians and representatives of al-Azhar - Egypt's major Islamic institution - and the Coptic Church.
"There is room in the country for everyone," ElBaradei told participants. "Reconciliation should not be limited to partners to the political process, but should include all Egyptians."
The Brotherhood and allied Islamists boycotted the meeting, saying they do not recognize the military-backed government.
The United States is concerned about the possibility of the protests leading to more violence, State Department spokeswoman Jen Psaki said in Washington.
"We remain focused on encouraging the interim government to move towards an inclusive process, which includes elections - civilian elections - and we're monitoring closely steps they're taking to do just that," she said.
The Pentagon said Wednesday it had halted the delivery to Egypt of four F-16 fighter jets, due to unrest in the country.
"Given the current situation in Egypt we do not believe it is appropriate to move forward at this time with the delivery of F-16s," spokesman George Little told reporters.
The jets were scheduled to be delivered Tuesday as part of a US military aid package. Defence Secretary Chuck Hagel informed al-Sissi of the decision by telephone, Little said.
Psaki said the decision was made by President Barack Obama and unanimously supported by his national security team. The US is examining whether Morsi's removal was a coup, which would trigger a legal requirement to cut off aid.
Meanwhile, three people were killed and more than 30 injured in Egypt, according to a senior health official, in the latest violence since the army deposed Morsi.
Two people were killed and three wounded in an attack on apro-Morsi march in Cairo, said Mohammed Sultan, the head of the government medical service.
Muslim Brotherhood Gehad El-Haddad alleged that plain-clothed police fired live ammunition at demonstrators.
Elsewhere, one police officer died and 28 people were wounded, when two bomb blasts hit a security building in the Nile Delta town of Mansura, Sultan told the independent newspaper al-Youm al-Saba.
In the Sinai Peninsula, where Islamist militants are active, three gunmen were killed on Wednesday when their car struck a landmine, an Egyptian security official said.
The blast took place near the town of al-Arish in northern Sinai, which borders Israel and the Palestinian Gaza Strip.
State media said the militants were killed when explosives in their car blew up.