New McLaren team principal Andreas Seidl says it's hard to see new manufacturers coming into Formula 1 with the new technical and sporting rules being discussed for 2021.
In recent years F1 has been trying to attract new companies such as Aston Martin, Audi or Volkswagen into the sport. But only Honda has actually taken the jump, returning to competition in 2014 to join Ferrari, Mercedes and Renault
It had been hoped that cost caps and less complicated engines might appeal to prospective manufacturers. But the way that the proposed new regulations are developing - such as the decision to retain the troublesome MGU-H - makes that increasingly unlikely, according to Seidl.
"[It's] very important to make sure you can enter this sport with an investment which is a lot smaller compared to what you have to do now," Seidl last week in Spielberg.
"The investment you have to do for the infrastructure, and the budget you have to use in order to get to the point where the established manufactures are - you have to be realistic.
"[It is] pretty difficult to imagine that anyone would invest that money at the moment," he admitted. "In general it's very difficult for a new engine manufacturer to come in."
Before taking up his post at McLaren this season, Seidl had been one of the leading figures at Porsche - another manufacturer that Formula 1 had hoped to attract into Grand Prix racing.
Unsurprisingly, Seidl didn't want talk about Porsche's plans directly: "Obviously I have a new shirt on, so I can’t comment on what happened at my previous employment."
However, he said that F1 still had a long way to go "in order to be attractive as a sport for a manufacturer to enter again."
And in the meantime, he was concerned that radical changes to the regulations might provoke one or more of the existing manufacturers to throw in the towel and walk away, leaving F1 in an even worse position.
"It makes sense at the moment to really keep the regulations as they are," he offered, suggesting that this was also the way to improve on-track competition within the sport.
"Keeping the regulations stable, all the powertrains are coming closer together," he pointed out.
"There are a lot of changes ongoing at the moment in the automotive industry with the powertrains, electrification and so on.
"We simply have to wait for the next cycle of the regulations," he added. "See how the automotive industry is going [and] if there is any chance to create interest for another manufacturer to come into this sport."
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