Toyota is crying foul after Ferrari won the fabled 24 hour Le Mans race last weekend after a decades-long absence.
El Mundo Deportivo newspaper reports that the Japanese manufacturer is upset about a late change that was made in the world endurance championship's 'balance of performance' system.
The change occurred just 10 days before the big race, with 37kg of extra ballast added to Toyota's Hypercar entry - representing an overall 16kg disadvantage compared to Ferrari.
Toyota chairman Akio Toyoda said: "Audi withdrew in 2016, Porsche disappeared in 2018 and only Toyota stayed at Le Mans to put up a fight.
"And we really welcome the return of other manufacturers this year. But this is motorsport. It is definitely not a policy that exposes the stubbornness of the manufacturers," the Japanese is quoted as saying.
"I wanted the drivers, engineers and mechanics to be racing in a place that looks to the next 100 years. But when I was looking at the rankings, I thought 'We lost because of politics'."
Toyota ambassador and well-known F1 personality Alex Wurz added: "Are we happy right now?
"No, because the balance of performance came at the last minute and we were surprised by the way it was announced and the timing, which is contrary to what we originally believed."