Lewis Hamilton has admitted that he is concerned his first taste of Pirelli's new wet tyres will be this weekend in China.

The weather forecast throughout the Shanghai weekend is poor, and Friday's opening session was indeed badly affected by rain.

Less concerned is Hamilton's current title nemesis Sebastian Vettel, who has snapped up every opportunity to help Pirelli test for this year's new rules.

"The reason why I'm generally happy to do it (testing) is because I love driving. So when there's an opportunity to test, even though it can sometimes be a bit dull, still it's better than sitting on the bike," said the Ferrari driver.

In contrast is Mercedes driver Hamilton's approach, with the Briton having cited injury niggles and car reliability issues as the reason for not extensively testing.

In China Hamilton said taking up the testing opportunities would have been "a waste of time", but he does admit to feeling "apprehensive" about the weather forecast for this weekend.

"I am not really looking forward to a wet track because I haven't driven on the new tyres. Usually I like driving in the wet, but I am a little bit apprehensive," Hamilton said.

"If you had to bolt them on for qualifying right now I have never driven them before. It is a much bigger tyre this year and there is a big risk that in the wet you damage the car.

"But I do relish the challenge and I believe if anyone is able to do it, I can, so I will figure it out."

Vettel, meanwhile, said that he will continue to snap up "every opportunity" to test, amid tight track-time restrictions in modern-day F1.

"That's personal, but I can't understand why you would reject it," said the German. "I think there's always something you learn, so the days I did with Pirelli to help them get feedback, for sure they also helped me."

Hamilton failed to set a time in this morning's first practice session.