I don't think this is to do with fear of a transfer ban - rather it is knowing this is one of those once in a generation players that Pep sees building a team around,
And giving Pep a squad of young talent that he can develop a team to become a winner around the world for years to come.
Whereby he will be desperate to commit long term to the club, which is what they want.
This is about building a dynasty for and with Pep to nurture.
Right now it is PSG and City waiting to jump onto the very top table.
This is City saying - it is our moment to get up there and stay.
I also think Mbappe might believe his best chance of developing into a long term mega star is both via Pep and keeping the core of his old Monaco team around him just in case some of his success was due to their play as well as his. Must be tempting to not have to try to recreate his last amazing season in a not entirely unfamiliar team.