Perez is backing Mourinho's complaints over their busy schedule.
Mourinho said: "I've not heard what the president said, because I don't read or watch anything on match days in order to stay focused, but if it's like I've been told, it could be an important speech for the future.
"If we are all together, and we feel the same difficulties, problems and injustices, we will surely be stronger."
He added: "A great club needs a great coach, but the great coaches are only that if they have a great club behind them.
"And to have the support of the president is very important for me."