The failure by Japan and the United States to settle their differences in talks in Tokyo last week on mad cow disease has given rise to fears that the import ban may be prolonged, and the dispute is fraying tempers on both sides.
Japanese sources said the U.S. government sent a powerful agricultural negotiating team to the talks as a way to put pressure on Japan to lift the import ban.
The delegation included Agriculture Undersecretary J.B. Penn, a former executive of a major agriculture consultancy.