Marseille chairman Pape Diouf is set to take action against his Lyon counterpart Jean-Michel Aulas over the French champion's alleged illegal approach towards winger Franck Ribery.
The French international has been constantly linked with a move away from the Stade Velodrome after the World Cup, with Lyon heading the queue for his his signature.
Reports suggest Aulas met with Ribery while he is in Germany with the France national team to discuss his transfer to the Stade de Gerland.
However, Diouf insists he has not given Lyon permission to talk with their player and has now accused Aulas and his club of tapping up the 23-year-old and is ready report the incident to the LFP.
"We can't accept that they have been in contact with a player that is under contract with us," Diouf told La Provence.
"We have fundamentals that show they have committed an offence."