CAIRO — Leaders of the Egyptian democracy movement vowed Sunday to escalate their pressure for the resignation of President Hosni Mubarak, even as his government portrayed itself as already in the midst of American-approved negotiations to end the uprising.

With the revolt entering its third week on Monday, several thousand protesters remained camped out in the central square that has been the epicenter of the uprising. While their numbers seemed smaller than on previous days, the protesters mustered enough support to form a human a human chain blocking entrance to the Mugamma, a huge edifice on Tahrir Square built in the 1950s to house the city’s labyrinthine bureaucracy — a central part of everyday life.

Outside the square, the authorities struggled to restore a kind of normalcy, with traffic flowing and snarling, and businesses reopening. But armored vehicles remained outside some government buildings and plans to reopen the stock exchange were postponed. News reports said the government, reorganized by President Mubarak in the early days of the uprising, would assemble on Monday for its first formal meeting.

On Sunday, the government announced that the transition had begun with a meeting between Vice President Omar Suleiman and two representatives of the Muslim Brotherhood, the outlawed Islamist group the Egyptian government has sought to repress for many years as a threat to stability. They met as part of a group of about 50 prominent Egyptians and opposition figures, including officials of the small, recognized opposition parties, as well as a handful of young people who helped start the protest movement.

While both sides acknowledged the meeting as unprecedented, its significance quickly became another skirmish in the battle between the president and the protesters. Mr. Suleiman released a statement — widely reported on state television and instantly a focal point in Washington — declaring that the meeting had produced a “consensus” about a path to reform, including the promise to form a committee to recommend constitutional changes by early March. The other elements echoed pledges Mr. Mubarak had already made, including a limit on how many terms a president can serve.

Leaders of the protest movement, including both its youthful members and Brotherhood officials, denounced Mr. Suleiman’s portrayal of the meeting as a political ploy intended to suggest that some in their ranks were collaborating.

Though the movement has only a loose leadership, it has coalesced around a unified set of demands, centered on Mr. Mubarak’s resignation, but also including the dissolution of one-party rule and revamping the Constitution that protected it, and Mr. Suleiman gave no ground on any of those demands.

“We did not come out with results,” said Mohamed Morsy, a Brotherhood leader who attended, while others explained that the Brotherhood had attended only to reiterate its demands and show openness to dialogue.

The standoff over the meeting underscored the conflicting narratives about the next chapter of the revolt that has shaken Egypt and the wider Arab world.

Each side claimed that it had emerged from the last 12 days as a survivor — unarmed protesters repulsed assaults first by police officers in riot gear and then by pro-Mubarak gangs in plain clothes, but Mr. Mubarak still emerged from a week of demonstrations that brought hundreds of thousands into the streets with his position and his Western support still intact. And while the government hailed what it called a return to normalcy, the protesters vowed that there was no turning back.

To rebut Mr. Suleiman’s claims of consensus, a group of young organizers whose Facebook page fomented the revolt — a half-dozen scruffy-looking doctors, lawyers and other professionals in their early 30s — stepped forward publicly for the first time. At least three had been released just the night before from three days of extra-legal detention at the hands of Mr. Mubarak’s police, and they vowed to escalate their movement. “The government played all the dirty games that they had, and the people persisted,” said Shady el-Ghazaly Harb, a 32-year-old surgeon. “We are betting on the people.”

More than 100,000 turned out again on Sunday in the capital’s central Tahrir Square — more than expected as the work week resumed here. And some of the movement’s young organizers, who were busy meeting to organize their many small groups into a unified structure, said they were considering more large-scale demonstrations in other cities, strikes or acts of civil disobedience like surrounding the state television headquarters.