Moto3 championship leader Jorge Martin will be joining KTM's Moto2 factory outfit in 2019.
Madrid native Martin, 20, has won two of the first three races in 2018 aboard his Gresini Honda and leads compatriot Aron Canet in the standings by seven points.
The current Moto3 season is Martin's fourth in the category, as he had moved up to the category after winning the KTM one-make series Red Bull Rookies Cup in 2014.
The KTM Moto2 deal includes the possibility of Martin stepping up MotoGP in 2021, provided he hits certain targets.
After finishing fourth in grand prix racing's lightweight class last year, Martin already had options to be competing in the Moto2 in 2018 - but decided against it in favour of a Moto3 title bid.
KTM's Ajo-run Moto2 outfit currently fields Miguel Oliveira and Brad Binder, who are fourth and eighth in the standings respectively.
The former is viewed as a prime candidate for a MotoGP ride with KTM's new satellite team Tech 3 next year, whereas Binder is likely to remain in Moto2, as teammate to Martin.