Speaking to reporters in Japan, the US Ambassador, Thomas Schieffer has delivered a consolatory message with regards to the Japanese ban on US beef, however, he warned US Congress was growing tired of the continued trade restrictions.

Just weeks after Japan's two-year ban of imports of US beef was lifted in January it was reintroduced when prohibited beef cuts were discovered in a shipment of veal.

Talking to a group of reporters in Japan, Schieffer said that the US was willing to consider allowing Japanese inspections of US beef plants to reassure Japanese consumers. He also said that the US investigation into the mishap would be completed within a week and a report would be given to the Japanese government post-haste.

"The whole investigation will be probably be concluded in the next week or so," Schieffer was quoted by Associated Press saying.

However, US concessions were accompanied by a veiled threat: Schieffer told reporters that he feared US Congress was growing impatient at continued trade restrictions. "There is no question in my mind that the American Congress has run out of patience," he said. "You don't want beef to be a contributing factor to the whole trade relationship running off the tracks."