Egyptian activists have called a mass rally in Cairo on Friday against the army's handling of protests that killed 17 people and drew international criticism of the ruling generals.
Protesters who fought soldiers and police in the capital for five days until calm was restored this week want the ruling military council to cede power more swiftly than planned.
Some Egyptians, sceptical of the military's avowed commitment to democratic change, want a presidential vote as early as January 25, the first anniversary of the start of the uprising that ousted Hosni Mubarak, or at least much earlier than the mid-2012 handover now scheduled.
Students have called for Egyptians to join Friday's protest with a march from Cairo's Ain Shams university, two of whose students were among the 17 killed.
Those two deaths prompted sit-ins on Ain Shams campus, in front of the Defence Ministry and at other universities.
The current predicament we have reached is a result of the army council's reluctance to play its role, its intentional foot-dragging, breaking its obligations and failing over the economy and security, putting the whole country on the edge of a huge crisis, said a statement signed by two dozen parties, youth movements and others calling for Friday's protest.
The April 6 movement, which played a lead role in galvanising Egyptians to rise up against Mubarak, said the army's handling of the latest street protests showed it was seeking to protect the previous regime.
BROTHERHOOD PARTY STAYS OFF STREETS
The Muslim Brotherhood's Freedom and Justice Party (FJP), leading in Egypt's staggered parliamentary election and wary of derailing the vote that will secure its place in mainstream politics, said it would not join in.
The ultraconservative Salafist al-Nour Party said on its Facebook page however that it would take part.
Many activists accuse the Brotherhood and other Islamists of betraying the protest movement in order to secure their own positions in the emerging new power structure.
The FJP said on its Facebook page it would not participate although it said it was the right of the Egyptian people to protest and demonstrate peacefully.
The party emphasises the need for the handover of power to civilians according to the will of the Egyptian people through free and fair elections ... in a stable environment, said Mohamed al-Katatni, a senior member of the FJP.
The comments indicated the Brotherhood was sticking to the army's timetable to hold a presidential vote in June. The Brotherhood has said bringing the vote forward could create chaos.
The Brotherhood may want to shape the new constitution before a presidential poll, seeking greater powers for parliament and avoiding giving the president too many powers, analysts say.
They add that an earlier presidential election would not necessarily eliminate the military's dominance in a new civilian-governed state.
The military has survived Egypt's political upheaval intact and has vast economic and other interests, so any new president would need its support to maintain order.
This is a transitional period where one party hands power to another. A deal must be struck. This is politics, a source close to the military said.
(Editing by Andrew Roche)