The 24-year-old, signed from Monaco for €186 million ($A295m) in 2018, a world-record fee for a teenager, continues to be linked with a move to Spanish giants Real Madrid, who tried to buy him in 2021.
In a statement sent to news agency AFP on Tuesday, Mbappe said PSG "were informed on July 15, 2022" of his decision not to extend his contract, adding that "the only aim of the letter was to confirm what had already been spoken about previously".
Earlier on Tuesday Mbappe dismissed reports saying he wanted to join Real in the close season transfer window, stating on Twitter: "I've already said that I'm going to continue next season at PSG where I'm very happy."
PSG now appear set to have to weigh up whether to sell Mbappe - who scored a hat-trick in France's defeat by Argentina in the World Cup final - or have him leave the club for nothing at the end of his current deal in June 2024.
The French club, owned by Qatar Sports Investments, have already lost Lionel Messi on a free transfer after the Argentina forward joined Major League Soccer's Inter Miami.
Reports in France had suggested PSG were hopeful of securing an extension to Mbappe's contract.
Real, who have already agreed a deal to sign England midfielder Jude Bellingham from Borussia Dortmund, could step up their interest in Mbappe following striker Karim Benzema's move to Al-Ittihad in Saudi Arabia.
