G.M., which has historically opposed import restraints, said it was not supporting the bill.
Heavy purchases of foreign plants and equipment resulted in import restraint from 1980 to 1983.
Voluntary import restraints on steel, which have been in place for years, will be among the first issues up next year.
Steelmakers are now seeking continued import restraints after a quota program installed by President Reagan expires Sept. 30.
It also objected to mandatory import restraints to retaliate against unfair trade practices.
American consumers are already paying $1 billion a year because of "voluntary" auto import restraints.
It is putting pressure on Tokyo to accept a system of "voluntary import restraints," but with a tough twist.
According to the policy institute's model, apparel retailers and importers, not consumers, would benefit most by the lifting of import restraints.
But many European auto makers say the import restraints, which would be similar to those in the United States, are far too generous to the Japanese.
Mr. Han said import restraints on about 540 farm and fishery products would soon be eased, on a step-by-step basis.