George Russell says Formula 1 is not yet ready to do away with tyre warmers, saying that such a move will bring about crashes and be dangerous for mechanics.
The FIA had originally planned to outlaw tyre warmers from the start of the 2024 season, though they may yet remain in the championship pending a final decision to be taken next month.
Mercedes' Russell, who also serves as a director of the Grand Prix Drivers' Association, took part in a test at Barcelona after the Spanish Grand Prix to test Pirelli's new blanket-less tyres, along with Mercedes reserve driver Mick Schumacher, and Ferrari's Carlos Sainz and Charles Leclerc.
Taking part in the test in early June temperatures immediately after a race weekend meant that Russell felt the conditions weren't fully representative of what might be experienced in cooler weather.
"In hindsight, it probably wasn't tested in the right conditions at the right circuit," Russell told media, including RacingNews365.com.
"If you go to a circuit such as Barcelona which is quite an aggressive tarmac, it was 40 degrees track temperature, fully rubbered in from race weekend, the tyres were very sketchy coming out of the pit lane, but by about Turn 5 on the out-lap it was at a respectable level.
"But if I compare that in contrast to the start of the year, when I did one run in Jerez in 10-degree track temperature, it was extremely difficult out of the pits."
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"There will be crashes"
The Briton also suggested that the tyres were not ready to be raced, citing the high probability of crashes and concerns over the safety of mechanics.
"If I'm being totally honest, I don't think we as a sport are at a position to bring these tyres into a racing scenario," said Russell.
"I will be very concerned for all the mechanics in the pit lane during a pitstop, I'd be very concerned for the out-lap in a race in cold conditions. There will be crashes, I have no doubt about it.
"There’s a lot of work and expense going into these tyres I feel like that could be put elsewhere."