Election officials in Honduras on Wednesday declared Nasry Asfura, a former mayor endorsed by President Trump, as the winner of the country’s presidential election, after weeks of delays, technical issues and claims of fraud.
Mr. Asfura became the Central American country’s next president by a razor-thin margin after a hard-fought contest between two right-wing candidates that was upended by Mr. Trump’s involvement, and a vote count that took more than three weeks to play out.
After the results were announced, Mr. Asfura said in a post on social media: “Honduras: I’m ready to govern. I won’t let you down.” At his party’s campaign headquarters, his supporters chanted, “Yes, we did it!”
Mr. Asfura’s opponent, Salvador Nasralla, said at a news conference on Wednesday afternoon that he would not concede or accept the results.
“This is the saddest Christmas for the Honduran people,” Mr. Nasralla said, claiming that some contested votes had not been counted before the final results were announced. “I am not calling for confrontation. I am not asking you to take to the streets,” Mr. Nasralla added. “But when we remain silent in the face of injustice, peace dies.”
The country’s electoral council said that more than 98 percent of the tally sheets had been processed and that it was “arithmetically impossible” to reverse Mr. Asfura’s victory. The final vote tally showed he had won by 27,000 votes, or a margin of less than 1 percentage point.
The election’s many technical problems, painstaking reviews of disputed tally sheets and many politicians denouncing the counting process stoked suspicions of election interference.
Outside observers flocked to Honduras for the Nov. 30 election, which they said defied predictions of meddling despite the accusations thrown around by each side.
“I have not found proof of widespread or large-scale fraud,” Héctor Corrales, the director of the Honduran research institute NODO who worked for the European Union’s electoral observer mission, said on Tuesday.
In a statement on Wednesday, Secretary of State Marco Rubio urged “all parties to respect the confirmed results so that Honduran authorities may swiftly ensure a peaceful transition of authority to President-Elect Nasry Asfura.”
If the results stand, the election would represent a victory for Mr. Trump, who endorsed Mr. Asfura, a construction entrepreneur, days before the election. Mr. Trump said on social media that they could work together to confront the “Narcocommunists” — a disparaging term for Honduras’s left-wing party and its allies in the region, including Venezuela — and bring aid to the country.
Mr. Trump also made a vague threat, saying that if Mr. Asfura didn’t win, “the United States will not be throwing good money after bad.” Since taking office again this year, Mr. Trump has assertively backed certain Latin American leaders as right-wing politicians have gained ground around the region.