Egypt’s military chiefs pledged Tuesday to speed up the transition to democratic rule, saying they will transfer power to an elected president by July 2012, a clear concession after four days of raucous street demonstrations.

The move was announced by the country’s military leader in his first national address since assuming power in February. But it appeared unlikely to deflate the anger of many of the tens of thousands of protesters on the streets of Cairo and in other parts of the country who have been demanding the military council’s immediate departure.

Speaking on state television in his green army uniform, Field Marshal Mohammed Hussein Tantawi appeared indignant, accusing demonstrators who have turned out in increasingly larger numbers of “insulting” the military. And he echoed the paternalism voiced by then-President Hosni Mubarak near the end of his three-decade rule, describing the armed forces’ hard work on behalf of the Egyptian people during the challenging transition period that has followed Mubarak’s fall.

A sea of protesters in Tahrir Square booed Tantawi as he finished speaking, and they erupted in chants calling for his ouster — a scene almost identical to those that played out during Mubarak’s final days. But this time, it was unclear whether those who braved tear gas to demand a change in leadership had the backing of the rest of the nation.

The dramatic events marked the most critical test yet of Egypt’s half-finished revolution, which has appeared orderly in contrast to the other Arab Spring uprisings that it helped spark, but which many Egyptians see as too slow.

And they deepened security concerns ahead of Monday’s parliamentary elections. The violent clashes between security forces and angry protesters have left 33 dead, at least 1,700 wounded and dozens under arrest. Among those detained were three Americans studying at the American University in Cairo, who were accused on state-controlled television of throwing firebombs during the demonstrations.

In Washington, the Obama administration applauded the Egyptian military’s decision to speed up the transfer to civilian rule. “These are reassurances that the Egyptian people and many of the political parties had been seeking for some time,” said State Department spokeswoman Victoria Nuland, adding that the United States “will hold the ruling authorities to the commitments that were made today.”

Although the military’s timetable for transition had been vague, it had appeared increasingly likely until now that the generals would remain in power until sometime in 2013. Tantawi also insisted that parliamentary elections would be held as scheduled on Monday.

Military officials also said that they had accepted the resignation offered Monday by the military-backed cabinet and that they will replace it with a new civilian government, which will serve until the military cedes power. But it was unclear whether that proposal had the support of political leaders across the ideological spectrum.

Clashes between protesters and riot police intensified Tuesday night, dimming hopes that the day’s announcement would put an end to what many have begun to call the second phase of the revolution.

“I don’t see any easy exit strategy,” said Heba Morayef, a Cairo-based researcher for Human Rights Watch. “The kind of trauma people are experiencing right now is one that will take some time to get over.”

‘We will not leave’

Tantawi warned against any attempts to destroy the “trust between the armed forces and the people,” and he defended the recent behavior of the police and the military, even as several human rights groups criticized the military’s actions.

“We never killed a single Egyptian, man or woman,” Tantawi said. “The Egyptian military believes it is part and parcel of the Egyptian people.”

Apparently confident of the military’s continued popularity among much of the public, Tantawi offered to hold a national referendum on whether the council should hand over power immediately, stressing that it did not want to rule. Its reputation has taken a hit, but the military is still seen by many Egyptians as the nation’s most trusted institution.

As Tantawi’s speech ended, many protesters responded in unison with loud chants of “Get out! Get out! We will not leave! He will leave!”

The continued unrest pointed to the possibility of a split between ordinary Egyptians facing tear gas and rubber bullets in the streets and a new collection of political leaders who have emerged since the revolution. But politicians who helped hammer out the deal said they hoped it would move the country toward a quicker transition to power without disrupting the elections.

The deal was brokered in a meeting Tuesday between the generals and political leaders, including presidential front-runner Amr Moussa, representatives of the Muslim Brotherhood’s Freedom and Justice Party, and several candidates from liberal parties and civic organizations. Notably missing was Mohamed ElBaradei, a Nobel Peace Prize laureate and former head of the International Atomic Energy Agency, who said in a statement that he sat out because he wanted to remain a liaison between revolutionary activists and the council.

After taking to the streets in a peaceful protest on Friday, the Muslim Brotherhood has urged members to sit out the demonstrations. Liberal critics charge that the Islamist party is not participating because it fears that doing so could derail the parliamentary elections, in which the party is expected to make a strong showing. But the Brotherhood may find itself in a difficult position, appearing to back the military council while trying to save face among fellow revolutionary forces.

Since the generals took power, the military has played a divide-and-conquer game, analysts said. Islamists have seen the council as a vehicle for emerging victorious in fair elections. Some liberals saw it as the only guarantor of a secular state. And the United States has seen the military as a crucial ally in an unstable region.

Moussa said he sympathized with protesters’ demands for the ouster of the military council, but he worried that if the generals stepped aside now, Egypt would have no one to take the reins of power. “For the first time there is a framework for the presidential elections and a time limit to an elected civilian government,” Moussa said. “Those are good steps — of course nothing is enough.”

‘Blood has been spilled’

In Alexandria, fierce battles continued Tuesday night as security forces bombarded protesters with tear gas. Demonstrators responded with rocks and firebombs. Protesters there declared an open-ended sit-in until the generals step aside.

In Cairo, protesters and security forces continued to clash on side streets leading to Tahrir Square. Huge plumes of tear gas hung over the square after an intense bombardment late Tuesday. But a few people appeared optimistic.

Ahmad el-Gammal, 27, speaking in Tahrir as he donated blood, said the military had convinced him that it would not derail democracy.

“Blood has been spilled,” he said. “Some people are here with a spirit of revenge.” He acknowledged that he was probably in the minority.

The editor in chief of the online Al Ahram newspaper joked that he only had to recall this winter’s 18-day uprising to understand what would happen next. Popular pressure would grow, said Hani Shukrallah, a noted analyst; Tantawi would give more speeches; and then he would finally step aside. “It’s a bad remake of the same film.”

Special correspondent Ingy Hassieb contributed to this report.