Cech has been linked with a number of clubs, including PSG and Real Madrid, following Courtois' return from three consecutive loan spells at Atletico Madrid and Goal understands Chelsea are ready to listen to offers for the 32-year-old.
Nevertheless, Mourinho claims he is keen to keep the shot-stopper at Stamford Bridge, though he hinted he would not stand in Cech's way if a bid was made by an opposition club.
"I hope nobody comes and I hope, as I was saying, I can keep two of the three best goalkeepers in the world which would be absolutely fantastic," he told Sky Sports.
"I think this goalkeeper with the history he has at Chelsea, he deserves every respect from us.
"But I think the first respect is to say clearly that we want him to stay because we want to have two top goalkeepers, plus obviously Mark [Schwarzer] which [sic] is a great goalkeeper and a great guy."
Mourinho also played down the selection of Courtois at Turf Moor and insists Cech has not asked to leave the club.
“I don’t like the word first-choice,” he told reporters. “Courtois was my first-choice today but when you have on your side a top professional like Petr, if you don’t perform, you are in trouble. They are both fantastic goalkeepers. I want to keep Petr here. Hopefully, he stays.
“No player is happy if they are not playing every game, sometimes if you give a player a rest they are not happy with that either. I don’t know a player who isn’t happy when not playing. Petr will not relax.
“He will not say ‘I have no chance. I’m expecting him to return on Wednesday and to be a top professional and fight for his place. Petr hasn’t asked to leave and I hope he doesn’t.”