General Motors Vice Chairman Robert Lutz, the automaker's product czar, confirmed the change in plans during an interview with Automobilwoche at the Tokyo Motor Show.
GM wanted to make minor changes to the current Opel Vectra then sell it in the USA under the Saturn brand name.
"It was a very good idea," Lutz said, "but it fell through due to problems with the American crash regulations."
"The US regulations were not taken into account when the Vectra was designed," said Hans H. Demant, Opel head of design development.
Opel / GM research shows that to comply with the US norms the Vectra's side sections would have to be modified and the front end would have to be lengthened by 10 centimeters.
"That would have been too expensive," Lutz said.
The project will be put on hold until the launch of the next generation Vectra.
The news for Opel and Vauxhall regarding the global GM Solstice project is no better. The roadster, which should have begun series production this November, will be delayed because it failed to meet new European pedestrian safety regulations that take effect starting in 2005.