The Tunisian forward signed a two-year deal with the Hoops on the weekend but there have been claims from Spanish club Levante that they had already secured his services.
Levante director Alberto Gill said yesterday that the club would take the situation to UEFA but Lennon has made it clear that everything is above board.
"There is nothing really to say," Lennon told Sky Sports News regarding the former Deprtivo La Coruna man.
"He is a Celtic player who did his medical yesterday and he is training this morning at Lennoxtown with the rest of the players who are here and we are very pleased to have him.
"When the story broke about Levante we were involved in the game (against Hibernian on Saturday) but having spoken to Peter (Lawwell, Celtic chief executive) and his (Lassad's) advisors everything is above board, it is the way we do our business anyway.
"Whether another agent got involved I don't know, sometimes these people do get involved and sort of muddy the water a little bit but as far as we are concerned everything was done the right way.
"I don't know what repercussions there can be, certainly not on our part anyway. I am assuming that the player is aware of the fuss."