CAIRO — An administrative court on Tuesday suspended a committee appointed to draft a new constitution, all but guaranteeing that Egypt will elect a president before it ratifies a new charter, and raising the stakes in the race.

After more than a year of street protests and political struggles, the court’s decision means that the future form of the government remains almost as unsettled as it was the day President Hosni Mubarak was forced from power. “We are in no sense any closer to a vision of what the future of the country is going to be like,” said M. Cherif Bassiouni, an influential Egyptian-American legal scholar at DePaul University College of Law.

Without revisions to the current Constitution, the winner of the presidential election scheduled for next month will technically assume the same powers that Mr. Mubarak wielded. As a result, whoever wins the presidential contest — and contenders include a leader of the Muslim Brotherhood as well as Mr. Mubarak’s former spy chief — may have unparalleled power to define the terms of the new charter and, thus, Egypt’s future.

The administrative court issued only a preliminary injunction, pending a fuller hearing, and legal experts said the legitimacy of the constitutional assembly would ultimately be decided in higher courts.

But the switch in the timetable — with the election coming first — particularly upsets the plans of the Muslim Brotherhood, the Islamist group that leads Parliament. After Mr. Mubarak’s exit, the group had pledged not to seek the presidency and instead began pushing for a system with a strong Parliament and a weak president. The Brotherhood expected to dominate the legislature and wanted a system entitling Parliament to name the prime minister.

Under the convoluted road map for the transition, laid out by Egypt’s military rulers, the Brotherhood-controlled Parliament named 50 lawmakers among a total of as many as 70 Islamists to the 100-person panel charged with writing the constitution. That group appeared set to swiftly approve a Brotherhood-crafted package of constitutional revisions in time to redefine the powers of the president before the election.

But the administrative court said Tuesday that installing 50 lawmakers on the panel appeared to violate the military’s constitutional declaration. The court ruled that the declaration required Parliament to appoint only outsiders. The current assembly is led by the same Brotherhood lawmaker who is the speaker of Parliament.

The ruling, however, was merely the final blow to the Brotherhood-led assembly. Although the Islamist domination of the assembly roughly mirrored the share of seats they won in Parliament, more than 25 other members walked out in protest two weeks ago, arguing that women, Christians and minority views were not adequately represented. Perhaps most damaging, among those boycotting the assembly were representatives of both the Coptic Christian church, whose members make up 10 percent of the population, and Al Azhar, the center of Sunni Islamic learning — a potentially fatal blow to its credibility.

The diminishing chances that the assembly would complete its work before the presidential election appear to be what motivated the Brotherhood last week to break its promise and run its own presidential candidate, Khairat el-Shater. No longer confident of being able to put in place a parliamentary system, the Brotherhood evidently felt compelled to seek the presidency as well. Mr. Shater was previously considered a top Brotherhood candidate for the prime minister’s job, but under the existing Mubarak-era Constitution, the president will continue to name the prime minister and cabinet.

Brotherhood lawyers initially said Tuesday that they would contest the court’s decision. But then Mr. Shater said in a statement that he respected the decisions of the judiciary.

The court’s decision did not appear to mandate a greater ideological diversity or to prevent an Islamist domination of the panel. But, in any case, the legal and political wrangling over the ground rules of the constitutional assembly is all but certain to push its work out past the election.

For liberals, the delay appears to fulfill a long-held demand that the military council governing Egypt since Mr. Mubarak’s ouster should leave power before the drafting of a new constitution, to prevent the military from using its position to shape the document in order to protect its own power and privileges.

But now the Brotherhood could gain even more influence over the new constitution, if it wins the presidency as well as control of Parliament. Human rights activists said they were especially apprehensive about the new candidacy of Omar Suleiman, Mr. Mubarak’s former spy chief with deep ties in the feared secret police.

“If there is anything we have learned over the last year, it is that every step of the way has to be a fight,” said Hossam Bahgat, executive director of the Egyptian Initiative for Personal Rights, a liberal advocacy group. “And we have not seen the end of this power struggle yet.” Mayy El Sheikh contributed reporting. (Copyright 2012 The New York Times Company 04/11/12)