Sebastian Vettel has blasted Pirelli after he suffered a high-speed tyre failure during the Belgian Grand Prix.
The German was set for a podium finish, but suffered a blowout soon after exiting Eau Rouge corner and finished outside the points.
However, Vettel is concerned that a driver could suffer a serious accident in the future, unless Pirelli act.
"Things like that are not allowed to happen," he told BBC Sport. "If it happened 200 metres earlier, I'm not standing here now, I'd be stuck in Eau Rouge.
"I don't know what else needs to happen. [Tyres are] a theme that keeps coming around, that nobody is mentioning, but is unacceptable."
Nico Rosberg also suffered a blowout near Blanchimont during free practice on Friday, but walked away uninjured.