Green underlined one of the main concerns about F1’s attempt to regulate future styling, namely that teams will always do whatever it takes to make their cars go faster.

That could lead to unexpected developments along the lines of the infamous “ugly noses” of 2012.

“They’re just concepts, drawings,” said Green when asked by Motorsport.com about the latest images. “What they look like, I’m not that fussed, it’s how they perform that I’m interested in.

"They’re just artistic impressions of what the cars might look like. I come at it from a technical side, I’m not interested in the styling side.”

Green admitted that teams are bound to come up with developments that impact the look that f1 has targeted.

"It will look nothing like what they’ve painted," he said. "The car at the front of the grid is usually the best-looking car, regardless of what it looks like.

“I honestly don’t know what direction they’re pushing in. I’ve only see a snapshot of a picture. This has come completely from the F1 Group.”

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Brawn himself admitted that it will be a challenge to keep on top of how the cars will look after teams pursue development.

“I’m not going to pretend that from day one we will have the perfect solution certainly from the aesthetics,” he said.

“Because try as hard as we can, we can never anticipate every move that the teams will make."

Green agreed that the FIA could have the 2021 technical regulations ready by the end of 2019, but cautioned that it would mean freezing concept development work much earlier than that.

“It would be well doable to write a set of regulations by the end of 2019, it depends whether they want to carry in the research behind it, to try and back up more of the direction they’re heading in. That’s the conundrum they’re heading in.

“To freeze the concept and start writing regulations means that they are freezing it very soon, and I don’t know whether that’s too soon.

"You want to give yourself at least six months to write the regulations.”