Formula 1 teams have been told that the reactive suspension system pioneered by Lotus has been banned for the 2012 season.
Sources have confirmed that a note was sent from the FIA to all teams on Friday evening indicating that the governing body was no longer satisfied the concept - which regulates ride height under braking - was still legal.
It is not clear why the FIA has decided now that the reactive systems should be outlawed, after AUTOSPORT revealed last week that it had given the green light to the Lotus idea as long ago as last January.
Rival teams are likely, however, to have made an effort to prove to the FIA that the Lotus system was in contravention of the regulations.
News of the FIA ban was first broken on The Flying Lap webcast, when Williams chief operations engineer Mark Gillan said on Friday night he had received a note from the governing body shortly before going on air notifying him of the move.
"The FIA has just banned that particular type of system," he said.
Speaking about Williams' efforts on the device, Gillan said: "We have been investigating that type of system for a while. It obviously has an impact on the aero platform of the car, [and] anything that gets the front ride height lower is beneficial from an aerodynamic perspective."
The reactive suspension system on the Lotus was first spotted at last year's Abu Dhabi Young Driver Test, and helped maintain the front ride height under braking for corners - to benefit both aerodynamic performance and stability.
Rivals teams were quick to look into the system, with Ferrari understood to be the first to propose its own version of reactive ride to the FIA.
Ferrari team principal Stefano Domenicali had said at his team's Wrooom media event in Italy last week that he was awaiting a response from the governing body on its legality.
He said: "What you are talking about, is more related to having stability under braking. It is a system that I know there have been some documents in writing between the FIA and the teams.
"We are waiting for the final confirmation if this kind of devices will be acceptable or not. But for sure we are looking around these sorts of devices to see if they contribute to a performance. But we need to wait and see what will be the reaction to the FIA on that."
Only this week, Red Bull Racing team principal Christian Horner had said he was unsure about the ultimate benefits of the system.
"It's like all of these things, it's about how they work and how they are integrated in the car," Horner told AUTOSPORT. "Things have to work as a package rather than as individual components. It appears to be an interesting concept but I'm the wrong person to be commenting on it."
When asked if he thought it was legal, he said: "I haven't had that close a look at it. That's more a question for [F1 race director] Charlie Whiting."
The Lotus system was mechanical and activated by brake torque. And, because it was part of the suspension system, was deemed legal at the time because it could not be classified as a moveable aerodynamic device.