President Hugo Chavez's radical challenge to the political order in Venezuela boiled over into street violence today with supporters of his plan to revamp the constitution clashing with elected lawmakers fighting to get inside the locked parliament building.

Security forces fired water cannons and tear gas to stop the confrontation outside the Capitol building, where backers of Chavez and National Guard troops sought to block members of the National Congress and their supporters from entering the building. Authorities said several protesters were injured in a shoving match that drew 200 to 300 shouting, stick-waving participants.

Chavez, a former lieutenant colonel and coup plotter who took office six months ago on a promise to bring "peaceful revolution" to Venezuela, appealed for calm in a speech broadcast live on television and radio. But the scuffles around the parliament building intensified a political confrontation touched off by his efforts to draft a new constitution and remake a government that he condemns as corrupt and out of touch with the people.

A newly elected constitutional assembly -- which is dominated by Chavez supporters and is the cornerstone of his proposed reforms -- issued an order Wednesday banning the opposition-controlled Congress from enacting new laws. The order restricted the duties of Congress, in effect transferring most legislative power to the constitutional assembly. That order followed a vote by the assembly last week giving itself broad new judicial powers as well, leading Supreme Court President Cecilia Sosa to resign in protest. The order concerning Congress would apply until congressional elections next year.

Defiant lawmakers from Venezuela's traditional political parties, describing the assembly's move against Congress as an affront to democracy, had vowed to cut short their summer recess and reconvene today in an effort to salvage their authority. But they were unable to enter the building and shelved their plans.

Congressional leaders met with representatives of the constitutional assembly Thursday night and most of today in an effort to reach a compromise over the future of Congress. By the end of the day, in an agreement brokered by the Catholic Church, it was decided that a 23-member congressional steering committee, which is dominated by the opposition, would select a special committee to hold talks with the assembly Monday about ending the impasse. Consequently lawmakers agreed to call off a special legislative session scheduled for Saturday that would have been a challenge to the assembly decree.

Chavez, 45, a charismatic populist who led an unsuccessful coup attempt in 1992, won a landslide victory in the presidential elections, riding a wave of discontent among the country's poor majority over corruption and mismanagement in this oil-rich nation of 23 million people. His ascendancy ended 40 years of domination by Venezuela's two main parties, Democratic Action and the Social Christian Party (COPEI), which are largely controlled by an economic and political elite.

The Clinton administration, which has taken a wait-and-see approach toward Chavez since he took office on Feb. 2, said this week that it is "deeply concerned" about the assembly's decision to supplant the elected Congress. In his speech this afternoon, Chavez said his government has no intention of disregarding civil liberties in Venezuela, a longtime democracy.

"The world must know that in Venezuela the rule of law is not being damaged and will not be damaged. . . . There is no authoritarian process here," Chavez said.

At the same time, Chavez insisted that the constitutional assembly is legally entitled to carry out sweeping changes, which include abolishing inefficient and corrupt public institutions. Referring to lawmakers' efforts to reconvene today, he asked, "Why call for an extraordinary session when Congress is in recess? This smacks of provocation."

"It is time to make room for new institutions and eliminate everything from the past 40 years, like the lies, the robbery, the misery, the hunger and the corruption," Pedro Garcia, 56, an unemployed Chavez supporter, said as he stood outside the Congress building, which was encircled by yellow police tape. "We want to rebuild this country from scratch, regardless of whether the old powers like it or not."

Chavez has remained extremely popular, with approval ratings of about 70 percent despite a recession and the loss of about 500,000 jobs since he took office in a country where about 80 percent of the population lives in poverty.

"We are in the minority but it does not give the government the right to crush the opposition that was legitimately elected," said Cesar Perez, head of the center-right COPEI party parliamentary faction. "The government just wants a caricature of Congress. We are not going to allow it. We prefer a dignified death and not a handicapped life."

But Aristobulo Isturiz, second vice president of the assembly, said, "We both have our reasons for today's meeting. But to deny the supreme power of the assembly seems to me absurd when the Supreme Court has already accepted it."