Peru’s President Dissolves Congress, and Lawmakers Suspend Him

President Martín Vizcarra of Peru ordered Congress to dissolve on Monday night, prompting lawmakers to try to suspend him and plunging the nation into uncertainty after a grinding, yearslong corruption crisis.

Opposition lawmakers responded to the president’s decision by accusing Mr. Vizcarra of staging “a coup” and moved swiftly to suspend him for 12 months. They nominated his vice president, Mercedes Aráoz, as the new acting head of state.

“I accept this with fortitude,” Ms. Aráoz said before Congress of a provisional presidency. “It is one of the most difficult decisions I have made in my life.”

It was not clear whether Mr. Vizcarra would accept the lawmakers’ decision. Speaking in a nationally televised address earlier Monday night, Mr. Vizcarra said the drastic move to dissolve Congress was his last recourse to force new parliamentary elections, which have been repeatedly blocked by the opposition-controlled legislature.

For years, a sprawling bribery case has roiled Peru’s politics and decimated its governing class, with former presidents arrested and a party leader jailed. In a testament to the country’s political dysfunction, the unelected Mr. Vizcarra — he took office after his predecessor resigned — has been trying to call for general elections since July, while the main opposition party has repeatedly avoided going to the polls.

“The closure seems a democratic solution to the problem that’s been plaguing the country for three years,” Mr. Vizcarra said Monday, after an emergency cabinet meeting. “Let the people finally decide who is right.”

Under Peruvian law, new parliamentary elections would be held within four months once the Congress dissolves. It was unclear, however, whether the lawmakers would comply with Mr. Vizcarra’s order and what actions the president was prepared to take to put the dissolution into effect.

Opposition lawmakers continued to occupy the Congress for hours after Mr. Vizcarra’s order. Some said they would resist any attempt to physically remove them, and threatened to depose the president for violating the Constitution.

“Vizcarra is trying to dissolve the Congress like any dictator,” the opposition lawmaker Juan Sheput wrote on Twitter during the congressional session on Monday night. Calling Mr. Vizcarra’s decision “outside the Constitution,” the lawmaker Alejandra Aramayo said during the session that “every decision taken outside the Constitution is a coup d’état.”

Mr. Vizcarra’s announcement prompted supportive rallies in the capital, Lima, and the mountain city of Cuzco, where celebrating demonstrators chanted “yes, we could,” according to videos posted on social media.

But despite that outburst of support, Mr. Vizcarra’s argument that the dissolution was necessary to protect the country’s democracy will likely stoke painful memories in Peru. In 1992, the country’s newly elected president, Alberto Fujimori, used a similar argument of national renewal to justify dissolving Congress; he then embarked on a long campaign of demolishing the country’s democratic institutions.

Mr. Vizcarra said the opposition majority in Congress left him with no choice. The main opposition party — headed by Mr. Fujimori’s daughter, Keiko — has blocked or ignored all his major attempts at economic and political reform.

Opposition lawmakers have also resisted new elections. When Mr. Vizcarra tried to trigger a new vote, Congress denied his petition.

A former vice president, Mr. Vizcarra was sworn in last year after his boss, President Pedro Pablo Kuczynski, resigned to respond to charges related to an international graft scandal involving the Brazilian construction giant Odebrecht. Lacking an electoral mandate, Mr. Vizcarra has since built his strong popular appeal on an antigraft campaign supported by a majority of Peruvians.

Under the country’s Constitution, Mr. Vizcarra will be unable to run in a new presidential election.

The clash on Monday was the culmination of a long-running conflict between a president who derives his legitimacy from popular support and a Congress that appeals to the Constitution, said Carlos Meléndez, an expert in Peruvian politics at the Diego Portales University in Santiago, Chile.

“It is a paradox that a politician with democratic values can end up weakening the democracy,” said Mr. Meléndez. “In his anxiousness for confrontation, the president is confusing his political rivals with the institution they represent.”