Four judges out of five voted to uphold the sentence, which could send Lula to prison in the coming weeks.
Judges of Brazil's Supreme Court rejected Tuesday the appeal presented by former President Luiz Inacio Lula da Silva's defense against a 12-year prison sentence previously issued over corruption and money-laundering charges.
The sentence against Lula, who remains the top candidate in all presidential polls including the latest Barometro Politico Estadao-Ipsos which put him ahead of the pack with 42 percent, was already appealed and confirmed by a previous court in January.
Candidates condemned over criminal charges are prohibited to run for elections according to Brazil's electoral law.
As a last resort, Lula would still be entitled to appeal the Supreme Court's decision at the Superior Federal Tribunal.
Lula has denied all the charges, arguing it was part of a political move aimed at preventing him to run for the presidential elections.
Lula launched his pre-presidential candidacy at an event hosted at Exominas in Belo Horizonte last month.
During his speech, he said that his “torturers,” in reference to judges, the corporate media and others who have pursued him on alleged corruption charges, can arrest “my flesh, but my ideas will carry on free. They will not detain our dreams.”