Formula One's governing body has moved to ban, before the start of pre-season testing, controversial new reactive suspension systems that several teams were working on.
Williams chief operations engineer Mark Gillan said the International Automobile Federation (FIA) had declared the systems to be illegal for the 2012 season starting in Australia in March.
"The FIA has just banned that particular type of system," he told Peter Windsor's The Flying Lap weekly live webcast on smibs.tv when asked about one reportedly being developed by Lotus.
Matteo Bonciani, the FIA's head of F1 communications, confirmed to Reuters that technical head Charlie Whiting had written to all the teams on Friday clarifying the situation.
He said the FIA had received a number of technical enquiries from teams about the legality of systems that could alter the configuration of a car's suspension in response to changes in brake torque.
Lotus, previously Renault, first tried out their system at a young driver test in Abu Dhabi last November but have not commented on its significance for the new car to be unveiled next month when testing starts in Spain.
Several others, including former champions Williams and the sport's most successful team Ferrari, were also believed to be looking into similar devices while awaiting an FIA ruling on their legality.
The issue had threatened to become the first big technical controversy of a year that will have an unprecedented six world champions, including Finland's Kimi Raikkonen returning with Lotus, on the starting grid.
Article 3.15 of the 2012 technical regulations, published this month, states that "any car system, device or procedure which uses driver movement as a means of altering the aerodynamic characteristics of the car is prohibited".
The Lotus system which first put the issue in the public eye was reportedly reactive to brake torque and formed part of the suspension.
"We have been investigating that type of system for a while," Gillan said. "It is obviously an impact on the aerodynamic platform of the car.
"Anything that gets the ride-height lower, particularly the front ride-height lower, is beneficial from an aerodynamic perspective."
Bonciani said systems shown to the FIA for approval relied on changes to the length of a suspension member and appeared to have a primary, if not sole, purpose of affecting the aerodynamic performance of the car.
Some systems designed to allow additional movement of the brake caliper for aerodynamic purposes were also illegal.
The governing body ruled that, in its opinion, the systems contravened article 3.15 and possibly articles 10.2.1 and 10.2.3. The latter article states that "no adjustment may be made to the suspension system while the car is in motion".