Peru socialist Castillo confirmed president after lengthy battle over results

The official result had been delayed by appeals from Fujimori aimed at annulling some ballots over fraud accusations. She said she was nonetheless bound by law to recognize the ruling of the National Jury of Elections.

"I proclaim Pedro Castillo as president of the republic and Dina Boluarte as first vice president," elections chief Jorge Salas said during a televised ceremony on Monday night.

Earlier in the day, Fujimori said she would recognize the official result "because it is what the law and the constitution that I have sworn to defend, mandates. The truth is going to come out anyway."

"They have stolen thousands of votes from us," Fujimori, the daughter of jailed former President Alberto Fujimori, told a news conference. She called on her followers to protest.

"We have the right to mobilize ... but in a peaceful manner and within the framework of the law," she said.

The Organization of American States, the European Union and Britain have all said the election was clean. The U.S. Embassy in Lima sent a tweet, welcoming the announcement. "We value our close ties with Peru and hope to strengthen them with President elect Pedro Castillo after his inauguration on July 28," the tweet said.

Castillo, in his first comments as president-elect, called for national unity. "I ask for effort and sacrifice in the struggle to make this a just and sovereign country," he said.

A 51-year-old former school teacher and the son of peasant farmers, Castillo has pledged to redraft the constitution and hike taxes on mining firms. Peru is the world's second-largest copper-producing nation But he has softened his rhetoric in recent weeks and hinted at a more moderate, market-friendly approach.

Castillo said on Monday that he would work toward economic stability.

"I ask that Keiko Fujimori not place barriers in the way, so that we may move forward and make this a government of all Peruvians," he said.