Mexico's electoral tribunal on Friday declared Enrique Pena Nieto the winner of the July 1 presidential election, one day after dismissing his leftist rival's bid to scrap the result.
"Enrique Pena Nieto is the president-elect of... Mexico, from December 1, 2012, to November 30, 2018," court president Jose Alejandro Luna Ramos said after the seven-judge tribunal unanimously validated the election.
Mr. Pena Nieto was scheduled to arrive at the court later Friday to receive his credentials. A few hundred protesters gathered outside the tribunal amid a heavy police presence.
Earlier, second-place finisher Andres Manuel Lopez Obrador refused to recognize the court's dismissal of his election challenge and called on supporters to join him at a September 9 rally in Mexico City.
Mr. Lopez Obrador claims that the Institutional Revolutionary Party (PRI) bought five million votes and violated campaign spending rules in order to secure Mr. Pena Nieto's victory.
"The elections were neither clean nor free nor genuine, therefore I will not recognize an illegitimate administration that emerged from votes that were bought and other grave violations of the constitution," he told reporters.
"Civil disobedience is an honorable duty when it is aimed against thieves who steal the hope and happiness of the people," he said.
But the court rebuffed his claims and confirmed that Mr. Pena Nieto defeated Mr. Lopez Obrador by 3.3 million votes.
"This electoral process was not free of problems, but they were adequately resolved within the law," said judge Maria del Carmen Alanis Figueroa.
Judge Flavio Galvan Rivera said: "It is my personal conviction that the election was free, fair and genuine."