CAIRO - Courts and factions in Egypt engaged Wednesday in a frantic last-minute scramble for power: The two highest appellate courts went on strike; the Supreme Constitutional Court accused the president of blackmail; the Islamist leaders of the constitutional assembly rushed to complete the charter by the end of the day, and the Muslim Brotherhood called for a major demonstration Saturday to show off its own political muscle.

The dueling marked an escalation in a two-front war pitting Egypt's Islamist president, Mohammed Morsi, against the country's courts and against a galvanized opposition in the streets that drew hundreds of thousands to Tahrir Square a day earlier in the biggest demonstration against Morsi since his election in June to replace the ousted Hosni Mubarak.

The uproar was set off by Morsi's attempt six days ago to declare his own edicts above judicial scrutiny and thus eliminate the last check on his power until the approval of a new constitution. But Morsi's gambit and the backlash are aimed at the looming deadline of Sunday, when the Supreme Constitutional Court is expected to issue a ruling that could dissolve the constitutional assembly and again upend Egypt's chaotic transition.

Morsi has said he meant to head off the possibility that the Supreme Constitutional Court might dissolve the constitutional assembly before it can complete its work. Courts have already dissolved the recently elected Parliament and an earlier constitutional assembly. And while some judges on the constitutional court are esteemed as impartial jurists, its members were all picked by Mubarak.

Rush fans the flames

The constitutional assembly's announcement of its intent to wrap up a draft constitution by Thursday has the potential to mitigate the institutional battle but inflame the political standoff. The assembly may produce a document that could be sent to a referendum even if the court dissolves the assembly, unless the court seeks to strike down the draft along with the assembly. Or the court might refer the fate of the assembly to another panel, the administrative court, prolonging the uncertainty.

But the assembly's rush is also stirring accusations that it is letting politics hasten the drafting. Many of the non-Islamists on the 100-member panel -- about a quarter, according to the best estimates -- have already walked out, damaging hopes that it might be presented as a product of consensus. Many have complained that the Islamists running the assembly were closing off debates in an attempt to push the document through before the court deadline.

Hossam El-Gheriani, the chief of the assembly, appealed for the boycotters to return for the final consideration Thursday, even though the Islamist majority in the assembly could pass the charter on its own. "Come back to us so that we welcome you and you can be our partner in issuing the constitution," he said. "This is your natural place from which you serve Egypt, not in your political party, in the street or the square; this is the square."

Game-changing strike?

However, Morsi's bid to extend his power over the courts for the duration of the assembly suffered a serious blow Wednesday when the Court of Cassation and the Cairo Appeals Court announced that they were joining a national judges strike in protest of his decree. They are the highest courts for appeals, and their judges are selected by their peers on the basis of seniority and accomplishment, so they cannot be dismissed as Mubarak loyalists.

Hossam Bahgat, the executive director of the Egyptian Initiative for Personal Rights, an independent human rights group, said the strike was "unprecedented and could be a game changer." Together with the demonstration the night before, Bahgat said, the court's action "dispels the myth the president is only opposed by Mubarak-appointed judges and 'liberal whiners.'"