CAIRO (AFP) – Tense Egypt braced Friday for a showdown in the streets between supporters of ousted president Mohamed Morsi and his army-backed opponents, who have called rival rallies across the Arab world's most populous country.
Tensions soared when the military reportedly gave Morsi's backers until the end of Friday to end sit-in protests they began after the army deposed the Islamist president on July 3.
Morsi's Muslim Brotherhood and allied Islamist groups have vowed to press their protests until he is reinstated and have sharpened the rhetoric by warning of "civil war", while calling for a huge turnout on the streets on Friday.
Army chief Abdel Fattah al-Sisi had earlier in the week set the scene for a potential showdown by calling for mass Friday rallies to give him a mandate, he said, to counter "terrorism and violence".
Western nations are watching the crisis in Egypt with growing unease, fearing the military's vow to return the nation to democracy may be little more than a fig leaf to mask a prolonged power grab.
The United States has refused to term the army's overthrow of Morsi a "coup," which would trigger an automatic freeze of some $1.5 billion in aid.
But it did finally send the interim leaders a veiled warning on Wednesday by suspending the delivery of four promised F-16 fighter jets.
"The interim government's strategy clearly consists of politically sidelining the Muslim Brotherhood until the elections," said German Middle East expert Michael Lueders.
He voiced fears Friday's rallies could explode into violence that could determine the nation's direction, saying Sisi was "playing a dangerous game" given the deep polarisation.
Although Egypt's military has insisted it was not targeting Morsi's supporters in its call for the rallies, the potential for bloodshed is large in a country that has been convulsed by violence in the past three weeks, with some 200 people killed since Morsi's ouster.
London-based rights group Amnesty International criticised Sisi's call for rallies, in a statement Thursday.
"Given the security forces' routine use of excessive force, such a move is likely to lead to yet more unlawful killings," said Hassiba Hadj Sahraoui, Amnesty's deputy director of its Middle East and North Africa programme.
Police said they would deploy in numbers to prevent incidents, as Morsi's camp sought to defuse tension by proposing a three-stage roadmap that would start with confidence-building steps.
Egypt's military, however, has upped the ante by setting a 48-hour deadline, which expires late on Friday, after which it will decisively deal with "violence and terrorism," according to a statement posted on a military-linked Facebook account.
Once the deadline expires, it said, "the strategy for dealing with violence and terrorism will change... appropriately to guarantee security and stability".
A senior army official told AFP the statement did not reflect the military's point of view, although it appeared on a "page with links to the armed forces".
"The 48-hour ultimatum is a political invitation," the officer said. "It doesn't mean after 48 hours we are going to crack down."
Many see the comments, however, as a warning that the security forces are planning to move in against pro-Morsi protesters who have been camped outside Cairo's Rabaa al-Adawiya mosque since his ouster.
On Thursday, the fugitive leader of the Muslim Brotherhood, Mohamed Badie, sharpened the tone by urging Egyptians to make a "stand for freedom and legitimacy, and against the bloody coup", although he insisted this should be done peacefully.
Senior Brotherhood leader Essam al-Erian said Morsi loyalists would not be intimidated by the army chief's call for mass rallies. "Your threat will not prevent millions from continuously protesting," Erian wrote on Facebook.
On a more conciliatory note, Hisham Qandil, prime minister before Morsi was toppled, Thursday proposed a three-stage roadmap that would start with confidence-building steps.
In a video recording posted on YouTube, the former premier said both sides should refrain from marches and hold rallies only in fixed locations.
He also called for the release of prisoners detained in the days leading up to Morsi's ouster by the military, and those detained since.
A delegation should be allowed to visit Morsi, detained by the army since his overthrow, to check on his health, he added.
UN chief Ban Ki-moon has demanded that Morsi and his high-level backers "be released or have their cases reviewed transparently without delay," said deputy UN spokesman Eduardo del Buey.