"The decision was not easy but I know that the right solution for me is to follow my other dreams within motorsport", the Finn writes on Instagram.
Rovanperä won the World Championship in 2022 and 2023.
Toyota writes on its website that the Finn will drive the Japanese superformula series next year.
"I know that it is a jump straight down into the deep, from rallying, but I look forward to it," Rovanperä says in a press release.
Rovanperä is currently third in this year's World Championship series in rallying.
