Felipe Calderon, who won by less than one percent of the vote, asked Mexicans to fight national problems like unemployment and crime.
Mexico's highest electoral court Tuesday made the outcome of the presidential election official, declaring Calderon the winner. The president-elect will assume office Dec. 1.
The court was widely expected to confirm the center-right Calderon defeated leftist former Mexico City Mayor Andres Manuel Lopez Obrador.
Obrador, however, contested the results, leading several days of protests in the capital and promised to create a parallel government. On Tuesday, Obrador reiterated that he would not recognize the Calderon administration.