Dr Helmut Marko has played down reports of trouble at Red Bull's new works engine partner Honda.

Auto Bild reports that Honda and an Austrian technical partner, Avl, have split due to a disagreement between engineers.

Red Bull's Marko confirmed the split, and also that Honda and ex-Mercedes engine chief Mario Illien are also no longer working together.

"Appropriate measures were taken to solve the problem," he insisted.

And Marko added: "Honda has already overtaken Renault and will be even better in 2019.

"Then Max (Verstappen) will have everything he needs. He is improving all the time. There seems to be no limit for him."