Reggina have reported Chelsea to the Italian Football Federation (FIGC) and UEFA over an alleged approach to one of their players.
The Serie A strugglers say 15-year-old Vincenzo Camilleri refused to play in a game for them and will have talks with Chelsea.
"He preferred to travel to London with his mother and a type of agent to reach a financial agreement with Chelsea," said President Lillo Foti. "We see this is an action of disloyalty and incorrectness."
Reggina are unhappy the player was allegedly 'tapped up' while he was still their player and aged only 15.
Camilleri had been expected to sign terms with Reggina when he turns 16 in March but now wants to join the English Premier League side.
"The player was contacted a couple of months ago when he was still our player," added Foti. "We have made complaints to the FIGC and to UEFA."
UEFA President Michel Platini expressed his regret over the situation. He told the Gazzetta dello Sport newspaper: "Young players should remain in the club they come from with their families, postponing their move to another club or another country until they are 20 or 22.
"Whoever makes that leap at the age of 14 can risk returning destroyed at 16, just because they didn't succeed."
FIFA regulations allow the transfer of 16 to 18-year-olds as long as it is between member states of the European Union.