Pirelli's wet weather tyres are a work in progress, with a revised compound set to be introduced in China, according to motorsport boss Paul Hembery.
As the official tyre supplier to F1, one of Pirelli's mandates this year has been to improve the quality of its wet rubber, while also managing a change in tyre structure and width on the back of F1's 2017 rule change.
Drivers have confirmed an improvement in the wet tyre's performance and quality, but Pirelli is still determined to work on further improvements.
"We have to change the working range of the compounds," said Hembery.
"We were going to do that on the full rain tyre anyway. It was something we had been working on, particularly knowing we have got the standing start [after safety cars].
"Plus some of the comments from last season were that the drivers can't switch them on when they come through. We have been working on that and what we saw today was that the intermediate was also struggling.
"That is an effect of the width of the tyre, because the inter was the one the drivers said, 'don't touch, don't change because we're very happy with it'.
"Now we know we probably need to alter as well to match it."
Hembery was hopeful to have a revised wet tyre in time for the China Grand Prix in early April.
"I believe we will have something ready for China in terms of the first compound change here, and what we have been developing will go to the final result as something we can introduce."
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