The court ruling came in response to actions filed by environmental groups and legislators arguing that the government commission that approved the $3.2 billion dam project last month had not taken into account a technical review.

The ruling temporarily halts the government’s approval process for the project, which set off large protests around the country in recent weeks.

Opponents applauded the ruling, hoping it was a step toward scuttling it altogether.

Amanda W. Maxwell, Latin America advocate for the Natural Resources Defense Council, based in New York, said the ruling was significant because the court was “the first authority in Chile to stand up to the behemoth project and to the intense political pressure to get it built.” She said the ruling indicated that the court “values the rule of law over private business interests, and sees no need to rush to build the dams.”

A lawyer for the project, Mario Galindo, told the Chilean newspaper La Tercera that the decision would do nothing to stop it. The ruling was “purely formal,” he said, “and there are no decisions about the legality or illegality” of the dam complex.

The HidroAysén project, proposed by an Italian-Spanish company, Endesa, and a Chilean company, Colbún, would build five facilities that would generate 2,750 megawatts of electricity. The energy would travel to Santiago over a 1,200-mile transmission line that has yet to be approved.

Critics contend that the project is environmentally destructive and unnecessary, and that Chile should focus on developing forms of renewable energy like wind and solar. The complex would be built in a region of Patagonia known for breathtaking glaciers and lakes that draws thousands of tourists a year.

But Chile, more than any of its neighbors in Latin America, is struggling to secure energy supplies to keep up with its economic growth. The country will need to double its capacity to generate electricity over the next 10 to 15 years, according to government projections.

Chile has little oil or natural gas of its own. Importing gas from Argentina has been unreliable, and the earthquake that damaged nuclear reactors in Japan this year has rendered building one in Chile unlikely, given its propensity for earthquakes.