Romain Grosjean has criticised a change to the tyre rules for 2019.

Pirelli says teams may no longer run temperatures of more than 80 degrees in the heating blankets for the rear tyres.

It is believed the change caused drivers to have grip problems when they exited the pits in Barcelona.

"I'm going to be hit on the knuckles for this but I don't understand why we're doing that," Haas driver Grosjean is quoted by France's Auto Hebdo.

"We do everything we can to make it safe but on Monday morning there were three of four cars spinning on the out-lap," he added.

"The temperature is very low, I think too low. The Pirelli tyres are already difficult to heat up so if you start at 80 and there is a safety car, you will end up at 50."

However, Grosjean's boss Gunther Steiner was less alarmist.

"He (Grosjean) was surprised but it's like everything in F1 -- you'll find a way around the problem.

"If Pirelli thinks it's the right thing to do, it's up to us to adapt," Steiner added.