This is announced by the club in a press release.
The Dutchman, with a past in among others Manchester United and Real Madrid, took over Leicester as late as in November, but leaves now after the club was relegated from Premier League.
According to Leicester, they have verbally agreed with the Dutchman to terminate the contract.
"I would like to thank the players in Leicester City, the trainers, the academy and everyone I have worked with for their professionalism and commitment during my time in the club. I also want to thank the supporters for their support and take the opportunity to wish the club good luck in the future", says van Nistelrooy in a press release.