Egypt President Mohamed Morsi is struggling to retain power in the face of a brooding people's revolution against his administration with the military threatening to take over.

Two years after a revolution in Egypt brought an end to the regime of Hosni Mubarak, several millions of Egyptians have again taken to the streets to protest against his successor and the Muslim Brotherhood.

The opposition Tamarod Campaign called for nationwide protests, civil disobedience and a march on the presidential palace if Morsi did not leave office by Tuesday.

Protesters have collected 17 million signatures, about four million more than the number of votes that won Morsi the presidency.

Analysts say Morsi became divisive, inept and authoritarian after he became president.

"That some of the revolutionaries are calling on the army to return to politics is a testament to how polarised Egypt is a year after the election of Morsi," Fawaz Gerges, director of the Middle East Center at the London School of Economics said.

"Think of the millions of people who cheered Morsi after his election.

"Think of the millions of Egyptians who pinned their hopes on Morsi.

"A year later, now, the millions of Egyptians who cheered for Morsi are saying he must go."

Siding with the voices of millions of Egyptians, Egypt's foreign minister Mohamed Kamel Amr on Monday joined five other ministers in resigning from Morsi's administration.

The military has also thrown its weight behind the opposition that has swarmed the famous Tahrir Square in Egypt's capital Cairo.

The soldiers told the country's civilian government it had until Wednesday evening to "meet the demands of the people" or it will step in to restore order.

This statement by the military and the increasing resignation of ministers undermines Morsi's ability to retain power in Egypt.

The military called the 48-hour ultimatum "a final chance to shoulder the burden of a historic moment in our country."

Army spokesman Colonel Ahmed Ali, said the military wanted a restructuring of the Morsi administration, reduced influence of the Muslim Brotherhood in his cabinet, and early presidential and parliamentary elections.

Protesters in Tahrir Square cheered as the military statements were read on radios and cell phones.

There were also cheers as y helicopters passed overhead Tahir Square.

Gerges argues that a military takeover "would plunge Egypt into a greater legal, political and institutional crisis."

However, the military says it would, if necessary, "prevent Egypt from slipping into a dark tunnel of civil unrest and killing, sectarianism and the collapse of state institutions."

In a statement on its Facebook page, Morsi's administration said Egypt was "moving forward" with a peaceful democratic transition.

But Gerges argues that peace could be restored if an opposition figure is appointed as prime minister, a new prosecutor-general is appointed, and the opposition-backed amendments to the country's constitution, which voters approved in December is implemented.

Morsi was elected Egypt's president in June 2012.