Brazilian President Luiz Inacio Lula da Silva confirmed his government had denied visas to two US officials who planned to travel to the country, accusing them of seeking to interfere in October's general election.

"This week we had to deny visas to two young folks they were sending to Brazil to meddle in Brazil's elections," Lula said at an event late on Wednesday.

Reuters reported last week, citing two Brazilian officials, that visa requests for the two officials in US President Donald Trump's administration had been rejected because they planned to cast doubt on the integrity of Brazil's electoral system.

A US State Department spokesperson at the time rejected any suggestion of a "ploy" to undermine Brazil's elections, calling the claims "baseless" and describing the visit as routine and consistent with the Bureau of Democracy, Human Rights, and Labor's statutory mandate.

Voters in Latin America's largest economy will go to the polls in October, when leftist Lula is set to face right-wing Senator Flavio Bolsonaro, a Trump ally and son of former President Jair Bolsonaro, who lost the last election to Lula.