By Yasmine Saleh and Marwa Awad
CAIRO, Dec 12 (Reuters) - Egypt's army chief will host national unity talks on Wednesday, seeking to end a growing political and economic crisis in the Arab world's most populous nation.
The meeting scheduled for 1430 GMT was called in response to a wave of protests since President Mohamed Mursi awarded himself sweeping powers on Nov. 22 to push through a new constitution shaped by his Islamist allies, which is due to go to a referendum on Saturday.
"We will not speak about politics nor about the referendum. Tomorrow we will sit together as Egyptians," armed forces chief and Defence Minister Abdel Fattah al-Sisi said at a gathering of army and police officials on Tuesday.
Mursi and the Muslim Brotherhood, which propelled him to power in a June election, were expected to attend, while the main opposition coalition said it would decide on Wednesday morning whether to participate. The opposition stayed away from an earlier reconciliation meeting called by Mursi last weekend.
Outside the presidential palace - where anti-Mursi protesters are demanding the Islamist postpone the vote on a constitution they say does not represent all Egyptians - there was scepticism tinged with some hope.
"Talks without the cancellation of the referendum - and a change to the constitution to make it a constitution for all Egyptians and not the Brotherhood - will lead to nothing and will be no more than a media show," said Ahmed Hamdy, a 35-year-old office worker.
But the fact that the army was calling such talks "is an indication to all parties that the crisis is coming to a head and that they need to end it quickly", he said.
Earlier, finance minister Mumtaz al-Said disclosed that a $4.8 billion International Monetary Fund loan, a cornerstone of Egypt's economic recovery hopes, would be delayed until next month because of the crisis.
The delay was intended to allow time to explain a widely criticised package of economic austerity measures to the Egyptian people, Said told Reuters.
Prime Minister Hisham Kandil said the measures would not hurt the poor. Bread, sugar and rice would not be touched, but prices of cigarettes and cooking oil would go up and fines would be imposed for public littering. In a bid to rebuild consensus, he said there would be a public consultation about the programme next week.
In Washington, the IMF said Egypt had asked for the loan to be postponed "in light of the unfolding developments on the ground". The Fund stood ready to consult with Egypt on resuming discussions on the stand-by loan, a spokeswoman said.
On the streets of Cairo, thousands of opposition supporters gathered outside the presidential palace to demand that Mursi postpone Saturday's referendum.
A bigger crowd of flag-waving Islamist Mursi backers, who want the vote to go ahead as planned on Saturday, assembled at two mosques and remained on the streets as night fell over the Egyptian capital. There were also protests in Alexandria and other cities.
The extended upheaval following the fall of Hosni Mubarak last year is causing concern in the United States, which has given Cairo billions of dollars in military and other aid since Egypt made peace with Israel in 1979.
State Department spokeswoman Victoria Nuland emphasised "deep concerns" over the situation in Egypt and repeated calls on protesters to demonstrate peacefully and on security forces to act with restraint. She declined to be drawn on whether Washington believed the referendum should be postponed.
The latest unrest has so far claimed seven lives in clashes between the Islamist Muslim Brotherhood and the opposition. But the Republican Guard has yet to use force to keep protesters away from the presidential palace, now ringed with tanks, barbed wire and concrete barricades.