Brazil's Federal Supreme Court on Thursday acquitted former President Fernando Collor de Mello of corruption charges.

The court said prosecutors had failed to prove the former leader, who was in office from 1990 to 1992, was directly involved in diverting public funds through public contracts.

"There is no proof or concrete evidence against the suspect, only unproven elements gathered during the investigations," the ruling said.

The Public Prosecutor's Office had accused Collor, together with other officials and a group of businessmen, of using fake names or frontmen to set up bank accounts to embezzle public funds.

National Deputy Attorney General Ela Wiecko said Collor, a member of the Brazilian Labor Party, knew about the scheme, which led to the recent conviction and sentencing of several party leaders. The case was known as the "mensalao," or monthly payout, in which funds were used to buy votes in the congress.

Collor stepped down as president in September 1992 to avoid impeachment and dedicated himself to clearing his name of the corruption charges.

A congressional committee designated to investigate the charges proved the existence of an illegal scheme coordinated by businessman Paulo Cesar Farias, who served as treasurer of Collor's presidential campaign.

Farias, who amassed a fortune through influence peddling, was later found murdered.