Muslim Brotherhood urges marches against Egypt military
The Muslim Brotherhood has called for mass protests across Egypt to demonstrate against sweeping new powers taken by the ruling military council.
Over the weekend, the generals issued two decrees dissolving the Islamist-dominated parliament and claiming all legislative power for themselves.
Youth activists have also been taking part in the protests.
Meanwhile, the camps of both candidates in Sunday's presidential election say their candidate has won.
A spokesman for the Muslim Brotherhood's Freedom and Justice Party (FJP) announced its chairman, Mohammed Mursi, had received 13,238,298 votes, or 51.74%, compared with former Prime Minister Ahmed Shafiq, who he said had 12,351,184 votes, or 48.26%.
The Higher Presidential Election Commission (HPEC) is scheduled to announce the official results on Thursday, but it usually shares them with the candidates beforehand to give them a chance to make objections.
The results tally with what Egyptian media and independent observers have been reporting, and the FJP's own calculations, which it released on Monday.
It will be a big surprise if Mr Mursi is not now declared the official winner, the BBC's Jon Leyne in Cairo reports.
However, Mr Shafiq's campaign vigorously denied their candidate had lost.
In a news conference shown on Egyptian television, representatives of Mr Shafiq's campaign said the papers that Mr Mursi's campaign referred to did not come officially from the HPEC, and insisted that Mr Shafiq was ahead in the tally.
"We are willing to do whatever necessary at a legal level to prove he's the next president," Shafiq campaign spokesman Karim Salem said.
The Supreme Council of the Armed Forces (Scaf) appears to be working on the assumption that Mr Mursi will win, our correspondent says.
It has made a series of decrees and appointments designed to reduce or constrain the power of the president, and entrench the power of the military.
Despite opposition talk of a "military coup", it may end up being a messy compromise that everyone can live with, our correspondent adds.
Voting over the weekend to choose a successor to Hosni Mubarak, who was forced to step down by last year's uprising, was overshadowed by two Scaf decrees.
The first ordered the immediate dissolution of parliament following Thursday's Supreme Constitutional Court ruling that the law governing the recent elections for the lower house was unconstitutional because party members had been allowed to contest seats in the lower house reserved for independents.
Troops were deployed outside the parliament building before the decree was issued on Saturday to prevent MPs gaining access. The FJP and the ultraconservative Salafist Nour party dominate both chambers.
The second decree, which was published after the polls closed on Sunday, amended the March 2011 constitutional declaration and gave the generals complete control over legislation and military affairs until fresh parliamentary elections are held.
The Scaf will also play a significant role in running the 100-member assembly that will draft the country's new constitution.
The new president - who will take office without the oversight of a parliament and without a permanent constitution to define his powers or duties - will be able to form and dismiss a government, ratify and reject laws, and declare war, but only with Scaf's approval.
The Scaf has also appointed a series of generals to the newly-established National Defence Council. While the council will still be chaired by the president, he will be able to be outvoted by members of the military.
Muslim Brotherhood members are set to protest against the decrees on Tuesday by taking part in a "million-man march" - the name they give for almost any demonstration in Egypt, our correspondent adds.
On Monday, Scaf officials restated its commitment to hand over power to the newly elected president by 30 June. Spokesman Maj-Gen Mamduh Shahin said the decrees were necessary "provisional measures".
"Circumstances were against us recently. The state of emergency is no longer in place and the constitutional court issued a ruling dissolving parliament, so we had to issue this supplementary constitutional declaration to arrange things for the coming period," he said.
He confirmed the Scaf had given itself legislative powers until a new parliament was functioning, but insisted these would be "restricted".