Egypt's military has given its president and his opponents a 48 hour "last chance" to reach an agreement to "meet the people's demands" before it intervenes in the dispute.
It described the mass protests on Sunday that brought out millions demanding president Mohammed Morsi's removal as "glorious" and said protesters expressed their opinion "in peaceful and civilized manner," and that "it is necessary that the people get a reply ... to their calls."
The military underlined it will "not be a party in politics or rule." But it said it has a responsibility to act because Egypt's national security is facing a "grave danger," according to a statement read out on state television.
"The Armed Forces repeat its call for the people's demands to be met and give everyone 48 hours as a last chance to shoulder the burden of a historic moment for a nation that will not forgive or tolerate any party that is lax in shouldering its responsibility," it said.
It did not directly define "the people's demands," but said if they are not realized, the military is obliged to "announce a road-map for the future and the steps for overseeing its implementation, with participation of all patriotic and sincere parties and movements"
It is the second ultimatum to be given to Mr Morsi and the opposition to reach an agreement. Last Sunday, defence minister Abdel-Fattah el-Sissi gave the two sides a week to reach an agreement. The organizers of Sunday's 's protests also gave him a Tuesday 5pm deadline to step down or face an escalation of the campaign to force him out, including civil disobedience.
Earlier protesters ransacked the Cairo headquarters of Mr Morsi's Muslim Brotherhood group. After clashes raged overnight, protesters managed to breach the compound's defences and storm the six-storey building, taking furniture, files, rugs, blankets, air conditioning units and portraits of Mr Morsi.
Smoke billowed out of the smashed windows of the fortified villa in the Muqatam district in eastern Cairo. A fire was still raging on one floor hours after the building was stormed. One protester tore down the Muslim Brotherhood sign from the building's front wall, while another hoisted Egypt's red, black and white flag out an upper-story window and waved it in the air in triumph.
At least 16 people nationwide have been killed in violence related to the protests, eight of them at the Brotherhood's headquarters.
Morsi critics view the Brotherhood headquarters as the seat of real power in Egypt, consistently claiming that the Islamist group's spiritual leader, Mohammed Badie and his powerful deputy, Khairat el-Shater, were the ones actually calling the shots in the country, not the president.