MONTEREY, Calif. — U.S. Agriculture Secretary Ed Schafer said Friday he wants to wait to see the results of an investigation into the nation's largest beef recall before making any policy changes, but he acknowledged that the debacle has delayed negotiations to ship U.S. beef to Japan and South Korea.

Those markets closed to the U.S. cattle industry in 2003 after a scare over mad cow disease.

Speaking before meat packers and processors, Schafer said the Westland/Hallmark Meat Co. recall announced earlier this week had already prompted diplomats to ask why the U.S. can't produce safe meat.

"As people look for reasons to protect their own market places ... they say you can't even send us safe meat," he said. "Do we need to issue new regulations and things? Right now we're just not prepared to do that."

Schafer, a former North Dakota governor, took office the day before the U.S. Humane Society released undercover video showing workers at the Chino-based slaughterhouse kicking and shoving sick and crippled cows and forcing them to stand with electric prods, forklifts and water hoses.

Downer cows, or those too sickly to stand, are banned from the food supply because they carry a higher risk of mad cow disease and other illnesses.

Sunday, the Department of Agriculture recalled 143 million pounds of beef from Westland, saying the agency had evidence that Westland violated health regulations. More than one-third of that meat was sent to school lunch programs.

No illnesses have been linked to the recalled meat, and authorities say the health threat is small.

Still, meatpacking industry officials worried the recall could affect global trade.

South Korea banned U.S. beef imports after 2003, citing concerns over mad cow disease. The illness has been linked to a rare and deadly nerve disease that has been blamed for more than 150 human deaths.

Japan's restrictions on American beef imports issued the same year have strained relations between the two largest economies. The country now allows only meat from cows 20 months old or younger.

Industry representatives feared the Westland recall would do away with gains President George W. Bush made in November, when Japanese Prime Minister Yasuo Fukuda had a state dinner at the White House.

"This thing came up and we all went 'oh, this is going to affect our trade,"' said Jeremy Russell, a spokesman for the National Meat Association, speaking at its annual convention in Monterey. "It's been four years since those markets closed, and people still have no idea when they'll open again. It's been the long winter of our discontent."

Russell said Westland belongs to the 400-member association, which represents slaughterhouses and meat processors in the U.S., Canada, Mexico and Australia. The recall has not only tarnished the company's reputation, but has hurt the image of the entire supply chain, Russell said.

Schafer said Friday he didn't want to make immediate changes to meat inspection regulations until the recall investigation showed who was responsible for the lapse in food safety.

He also rejected charges that chronic staff shortages among inspectors were endangering the public by allowing sick cows to get into the nation's food supply, and said the USDA meat inspection system was intact.

"Certainly when we have limited resources because the people of the United States can only afford so much tax burden, people get stretched," he said, speaking Friday afternoon after eating lunch with schoolchildren at a Salinas elementary school. "I am confident that the job is getting done."

Martin Luther King Jr. Elementary Academy served chicken hot dogs Friday, rather than risk serving the beef they purchased from a vendor supplied by Westland, administrators said.