Japan has agreed to allow U.S. beef imports, which were first suspended in December 2003 due to mad cow concerns, but it attached strict conditions such as limits on the age of the cattle and removal of risk material such as spinal cords.

Friday's suspension comes as Washington steps up pressure for Tokyo to relax its rules.

The beef tongue accounted for four out of a total of 250 boxes that were shipped by Cargill's plant in Dodge City, Kansas, Japanese ministries said.

They said the beef tongue was accompanied by documents written in Spanish, suggesting the shipment had been sent to Japan by mistake.

"Shipments that were not destined for Japan were included," said an official at the Japanese health ministry.

"We'll suspend imports from that facility after the incident," the official said. The length of the suspension, which was not the first to be imposed by Japan since the ban was lifted, was unclear.

Japan has already taken one facility off the list of 35 meatpackers that U.S. authorities had approved as beef exporters to Japan, after the plant exported an ineligible cargo.

American beef has been available in Japan since Tokyo lifted the ban last July, although the United States is far from recovering its pre-ban status as a leading foreign beef supplier.

Source: Reuters AlertNet