(Adds details from letters to Chinese, Russian officials)
WASHINGTON, May 1 (Reuters) - China and Russia should end restrictions placed on U.S. pork imports after an outbreak of a new flu virus, U.S. Commerce Secretary Gary Locke said on Friday, noting the flu cannot be spread by food.
"Government actions during this time of economic uncertainty and international concern about influenza must be based on scientific evidence," Locke said in letters to Alexei Kudrin, the Russian Federation's deputy chairman, and Chen Deming, China's commerce minister.
"There should be no restrictions on trade without cause," Locke wrote to the officials, each of whom recently met with Locke in Washington.
Locke also said he talked about the bans with Chinese Ambassador Zhou Wenzhong at a meeting on Thursday evening.
World and U.S. health officials have said there is no risk of spreading the flu through food, and there have been no reports of the flu in U.S. swine herd, Locke said.
More than a dozen countries banned U.S. pork after the flu outbreak, which had been called "swine flu" until officials took steps to refer to it by other names.
The bans have cut U.S. pork exports by as much as 12 percent. China and Russia, which account for nearly 20 percent of U.S. pork exports, have caused most of the disruption.
Russia banned all raw meat, including beef and poultry, from California, Texas and New York, as well as all pork from Alabama, Arizona, Arkansas, Georgia, Indiana, Kansas, Louisiana, New Jersey, New Mexico, Ohio, Oklahoma and Florida. [nN30515599]
China banned pork and swine that originate or are shipped through California, Texas, Kansas, New York and Ohio. (Reporting by Roberta Rampton; Editing by Marguerita Choy)