U.S. did not raise auto rules of origin at NAFTA talks -source

WASHINGTON, Aug 19 (Reuters) - In the opening NAFTA session of talks, the United States did not raise its previously stated demands to boost North American content for autos, a source directly familiar with the negotiations said on Saturday.

A top U.S. official had said on Wednesday that Washington wanted tougher rules of origin, which determine how much of an auto must be built in the three NAFTA nations, as well as new measures to ensure "substantial U.S. content" for autos. (Reporting by Anthony Esposito and David Ljunggren; Editing by Lisa Von Ahn)