On Thursday the FIA presented an outline of the all-new 2026 F1 cars with a bigger emphasis on electric energy and much lower drag and downforce levels.
The more slippery cars are projected to be slower through the corners, but faster on the straights than the current machinery, which Russell believes comes with safety implications.
"The cars are going to take a quite a big turn in terms of how they perform," said Russell, also a director of the Grand Prix Drivers' Association that represents the drivers' interests.
"They're going to be exceptionally quick in the straights, 360km/h probably at most tracks, which is pretty impressive.
"Obviously then the safety needs to be probably improved, because having a crash at 360, 370km/h is going to be pretty crazy."
A particular point of concern is what could happen on ultra-fast street circuits like Jeddah and Baku, with Russell urging the rule makers to rethink whether even faster top speeds are really a desired by-product of the 2026 rules shift.
"When it comes to safety, unfortunately, history has told us that incidents need to happen before changes are made," he explained.
"Everybody needs to do a really thorough job ahead of these regulations, because the cars are going to be so quick.
"It's going to have so little downforce in the straights, it's almost going to feel like you're just flying through the air.
"You can imagine in a race that it starts raining and you're on slick tyres, and you're doing 250 miles an hour on a street circuit. That's going to be a bit of a sketchy place to be, so these are questions that need to be answered.
"To be fair to the FIA, they are fully aware of this and they're on top of this, and they're looking at all of the possible scenarios of what could happen.
"Time will tell, but the cars are already bloody fast as they are. Where do we stop, are we going to get up to 400 kilometres an hour? Do the fans really need or want to see this?"
Russell felt it would be a shame to lose the high-downforce performance of the current generation of cars, but said it would be a worthy compromise if it means the quality of the racing improves.
"From a driving standpoint you want the fastest cars, you want to feel like you're in a fighter jet and in 2020 and 2021 that's how it felt, and now these cars are getting very quick again," he added.
"It would be a shame to lose some of that performance of the car. But on the flip side, it will improve the racing if there's less downforce and there's less dirty air.
"You can't have it all and you've got to choose your battles. What is it that we want to achieve?
"For me, you want to have good, hard racing, and strong competition, ideally, between every team and every driver."
Watch: The Future of Formula One - First Look at The 2026 F1 Regulations
