Guardiola has signed terms this week to 2023.
Mourinho said: "The only certain thing is that no one has put a gun to Pep's head to get him to sign the contract.
"If he does it, it's because he is happy to do so. He knows what he will have ahead of him for the future. He has a motivation.
"If he continues it's because he's happy to do it, so I'm happy for him."