Brazilian President Luiz Inácio Lula da Silva is facing a legal challenge at the start of the election campaign over a Carnival parade dedicated to him.

Brazil's Superior Electoral Court accepted a complaint against Lula, Brazilian media reported on Monday. The liberal opposition party Novo accuses the president of unlawfully promoting himself through the publicly funded parade at Rio de Janeiro's world-famous Carnival.

Lula, 80, is seeking a fourth term as president in October as the candidate of the left-wing Workers' Party (PT).

During the February parade, samba school Acadêmicos de Niterói traced Lula's rise from a metalworker to president of Latin America's largest economy. A giant sculpture of Lula with a raised fist was carried through Rio's Sambadrome.

According to media reports, Novo leader Eduardo Ribeiro said the parade was not a mere coincidence or a spontaneous show of political support, but involved millions of reais in public funding for a samba school whose theme was dedicated to Lula.

Ribeiro also wrote on X that the "megalomania of a politician who thinks he is bigger than Brazil and promotes a parade worthy of a communist dictator" could make Lula ineligible to stand for election.

According to CNN Brasil, the president now has five days to respond to the allegations.

Opposition parties had already tried unsuccessfully during Carnival to stop the parade over allegations of premature campaigning. Under Brazilian law, campaigning for a candidate is only permitted after the candidate has been formally nominated. Lula had not yet been officially selected at the time.

The presidential election is due to take place on October 4. Right-wing politician Flávio Bolsonaro, son of convicted former president Jair Bolsonaro, is seen as Lula's main challenger.