Brazilian prosecutors have charged the world's richest banker, Joseph Safra, for allegedly agreeing to pay more than $4 million in bribes to tax auditors to reduce or annul fines on unpaid taxes.

The Federal Prosecutor's Office said in a statement Thursday that Safra knew of a 2014 plan by executives at Banco Safra to pay 15.3 million reals ($4.25 million) in bribes. Also charged was former bank executive Joao Inacio Puga who allegedly negotiated the bribe-payment scheme.

Prosecutors said Safra was not directly involved in the bribery negotiations, but taped conversations showed that Puga reported to Safra on the bribery talks.

The Safra Group, Safra's investment holding company, said in a statement that the charges filed by the prosecutors were "unfounded," and that no inducement was offered to auditors nor did the Safra Group receive any benefits.

Safra's fortune is estimated at about $18 billion by Forbes Magazine.