(CAIRO) -- The days of Egyptian President Mohammed Morsi's regime could be numbered if he doesn't reach a compromise with the millions of his countrymen calling for the Islamist leader to step down.
A second day of massive demonstrations in Cairo and elsewhere spurred Egypt's Supreme Council of the Armed Forces to deliver an ultimatum that the military will intervene unless Morsi agrees to unspecified demands by his political opponents within 48 hours.
Morsi has said he would reject the ultimatum, but the crisis appears to be growing as Foreign Minister Mohamed Kamel Amr reportedly submitted his resignation, according to Egypt's state news agency Mena. Already, five Morsi Cabinet members have offered to quit.
The chief complaint is that the government run by the Muslim Brotherhood is more concerned with turning Egypt into an Islamic state than solving economic and political woes.
Morsi has remained defiant, refusing to back down from demands to hold early presidential elections. He contends that if he is ousted in a revolution, the same fate will befall all subsequent Egyptian leaders.
However, it was the so-called "Arab Spring" of 2011 that pushed Egyptian President Hosni Mubarak out of office in under three weeks.
The demonstrations, which have turned violent in some areas of the country, marked the one-year anniversary of Morsi rising to power in a free election.
Traveling in Tanzania, President Obama remarked, "Although Morsi was elected democratically there's more to be done to create a condition where everyone feels their voices are heard," adding that the U.S. supports a democratic Egypt, not necessarily a leader.
When asked what might happen in Egypt over the next 48 hours, Pentagon press secretary George Little said the U.S. was still reviewing the ultimatum.
Little told reporters, "We are supportive -- as the president has said -- of the democratic transition in Egypt and this process requires compromise on everyone's part. And we hope that all Egyptians find a way to work peacefully to address the issues that the country's facing."
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