The nation's restaurants will urge the government to ease import restrictions on U.S. beef, saying the stringent rules are causing a serious supply crunch, officials said Tuesday.

Although the government eased a 2 1/2-year blanket ban on U.S. beef in July, lingering trade restrictions over mad cow fears have meant only a trickle of U.S. beef has made it into the country.

The Japan Food Service Association and three other restaurant groups say supply of U.S. beef has lagged critically behind demand and driven prices higher. They plan to submit a petition to the health and farm ministries as early as Friday demanding import restrictions be eased, according to JFSA official Kunio Chiba.