It has been no secret that Los Blancos have been looking to make Mbappe their next big 'Galactico' following the departure of Cristiano Ronaldo in 2018.
The Spanish club made a couple bids in the recent transfer window, which were both rejected but Leonardo was not happy with how Madrid have conducted themselves in the last two years.
"At Madrid they are denying it, but I think that Real Madrid have been trying to sign Mbappe [as a free agent] for a while," the Brazilian told Gazzetta dello Sport.
"They have been talking publicly about Mbappe for two years. That should be punished.
"I see it as disrespectful towards Mbappe. He is not just another player, he is one of the best players in the world.
"The coach, the board, Real Madrid's players have spoken about Kylian... I think it is part of their plan. It is not respectful."
It's not the first time Leonardo has discussed Madrid's pursuit of Mbappe, with the Brazilian telling L'Equipe on October 6: "It's been two years that it lasts, I remind you that the transfer window is over.
"There are matches and Real Madrid cannot continue to behave in this way. May it stop! Mbappe is a PSG player and the club fully understands that this relationship will last.
"These new comments are just the continuation of a lack of respect towards PSG and towards Kylian Mbappe."