Michelin says it would be interested in a return to Formula 1 if the sport's technical regulations were changed.
The French tyre manufacturer has been out of grand prix racing since the end of 2006, and has been reluctant to get involved again unless it faces competition.
But in a hint that a comeback as a sole tyre supplier is not impossible, Michelin's motorsport director Pascal Couasnon says that if F1 has an overhaul then it could be tempted.
"We are open to it," he told Italian publication Autosprint. "But there are certain conditions.
"Formula 1 needs to change the technical regulations. The tyre must again be a technical object rather than a tool for a spectacular show."
He added: "We want 18-inch tyres that we will use in Formula E, and soon in other series.
"If Formula 1 takes our proposals into account, then we are prepared and we have a strong will to return.
"If things stay as they are, we are not interested. So we will submit our application, then it's up to (Bernie) Ecclestone and the FIA whether they accept or not."
New tyre characteristics
Couasnon also made it clear that Michelin would want a big change of philosophy about how tyres perform in F1.
"[They] should have a stable performance and grip level. It is not normal for drivers to say after a few laps 'I have to slow down to save the tyres'," he said. "This should not be.
"Today Formula 1 drivers cannot show their talent because the tyres do not allow it.
"This happens when there is only one manufacturer and no motivation to improve. But if there is a technically interesting rulebook, then you have to develop your best product even if you are the only supplier."