The family firm of President Mauricio Macri allegedly tried to empty the accounts of Argentina's postal service, which it ran years ago, the justice ministry said on Saturday.
The accusation by a prosecutor handling commercial matters, Gabriela Bouquin, stems from a contract the Macri Group had to manage Correo Argentina between 1997 and 2003, before the illiquid service was re-nationalized.
She said that there were transfers of nearly $300,000 from Correo Argentina's accounts in 2016, mostly to firms controlled by Macri family-owned company.
The transfers were stopped by a judge appointed to oversee Correo Argentina's finances.
In June 2016, the government agreed to forgive $296 million of debt run up by Macri's family company in a controversial accord. Bouquin has previously criticized that controversial accord as "abusive" and "ruinous" for the state.
Mauricio Macri, who took office in December 2015, has denied any conflict of interest regarding his business holdings, which span construction, farming and aeronautics.
He handed over his shares in the family group to three of his children before his election.