Leonardo has lost the appeal against his nine-month ban for shoving referee Alexandre Castro in the tunnel following Paris Saint-Germain´s 1-1 Ligue 1 draw with Valenciennes on May 5 and will now be suspended until June 2014.
The Brazilian was initially handed a nine-month suspension for the incident on May 31, but that has been extended by the French Football Federation (FFF).
"The High Commission of Appeal of the French Football Federation on Wednesday decided to suspend Leonardo, sporting director of Paris Saint-Germain until June 30, 2014," a statement on the FFF website reads.
Leonardo's punishment applies to all official duties surrounding his role, while he is also not permitted to stand on the touchline during matches.
PSG was also given a suspended three-point deduction as a result of Leonardo's actions.
The 43-year-old has been an integral figure in PSG's rise to the top of the French game, luring a number of high-profile players - including Thiago Silva and Zlatan Ibrahimovic - to the Parc des Princes since his arrival in July 2011.