Bloomberg News has reported that California has amended its zero-emission vehicle mandate, pushing back the start two years and easing some requirements in the hope that car makers that have sued to block the program will reconsider their opposition. According to Bloomberg News, the program requires that 10 percent of cars sold in California by the six biggest makers emit almost no pollution from the tailpipe or from gasoline evaporation. General Motors and DaimlerChrysler AG were joined by the US Justice Department last year to win a federal injunction temporarily blocking California's Air Resources Board from enforcing the rule. According to the proposal, California said it would delay the program's start until 2005 from 2003, halve the required number of pollution-free cars, and make it easier for companies to comply by offering more hybrid-electric cars, the news agency said. According to Bloomberg News, a General Motors spokesman declined to say whether the changes would affect the company's suit with DaimlerChrysler, filed with a US district court in Fresno, California, in January 2002. The suit alleged that the state's emissions program attempted to regulate fuel economy, violating the Energy Policy and Conservation Act of 1975 that permits only the federal government to set such standards. All references to fuel economy have been removed in the latest version of the plan, first proposed in 1990, Air Board spokesman Jerry Martin told Bloomberg.