"We believe these were isolated incidents," he told reporters.

South Korea was sending back 66.4 tons of U.S. beef that failed to meet export verification standards established between Seoul and Washington. The products were apparently processed for domestic consumption but were shipped out as exports by mistake.

"There are going to be some start-up speed bumps," Johanns said. "I am very confident that we can get them (South Koreans) the information that they need." Seoul lifted a two-year ban in January last year on U.S. beef imports, imposed after the discovery of mad cow disease on an American cattle farm. The ban remains in effect on bone-in products and meat from cattle over 30 months old.

The mistaken shipment contained bone-in chuck short ribs.

U.S. press reports identified the shipper as Am-Mex Service Co. of California, and the U.S. Department of Agriculture said it was looking into the case, including why inspectors signed the papers allowing the export to South Korea.

"The products were clearly labeled for domestic consumption," department spokesman Keith Williams was quoted as saying.

Source: Yonhap News

For previous news on this storyline, click here.