Kirk, the top U.S. trade negotiator, urged all trading partners to base any food safety measures taken to protect their populations on scientific evidence and in accordance with their international obligations.

"Restrictions on U.S. pork or pork products or any meat products from the United States resulting from the recent outbreak do not appear to be based on scientific evidence and may result in serious trade disruptions without cause," Kirk said.

The swine flu outbreak began in Mexico and has spread globally. The latest CDC data showed that there were 65 confirmed cases of human swine flu infection in the United States, none of them fatal.

In response to the outbreak, the WHO raised the worldwide pandemic alert level late Monday to Phase 4, signaling an increased likelihood of a pandemic.

-- Click for more news in Tech Max >>

Editor:Yang Jie