SEOUL, South Korea (CNN) -- No U.S. beef will exported to South Korea until the countries agree on limiting shipments to meat from cattle of a certain age, South Korea's agriculture minister said Tuesday.
Protesters at a Sunday demonstration in Seoul against U.S. beef imports.
That effectively keeps in place -- at least for now -- a five-year ban on American beef products that was installed over a case of mad cow disease in the United States in 2003. The agriculture ministers statement marks a change from a recent deal to resume beef imports with no age restrictions.
"Because the public is most concerned about meat from cattle over 30 months old, we have asked the United States not to export that kind," Chung Woon-chun, South Korea's agriculture minister, told reporters Tuesday, according to the Yonhap news agency.
Tens of thousands of people in South Korea have protested the governments plan to import beef from the United States.
CNN contacted the U.S. Embassy in Seoul for comment on the decision, but no one was immediately available to respond.
On Monday, the South Korean government put off the final administrative step needed to resume imports. Without that step taking place, no beef will be imported from the United States.
Washington and Seoul reached an agreement in April that bans the import of high-risk materials, like tonsils, brains, spinal cord marrow and a section of the small intestine. It put no age restrictions on the cattle.
Animals more than 30 months old are considered at a greater risk for mad cow disease, which can be transmitted to humans.
Soon after last week's announcement, thousands of people responded with regular protests, chanting "We don't want crazy cows."
Authorities dispatched more than 10,000 riot police everyday to keep the peace, Yonhap said.
More than 40,000 protesters gathered in central Seoul late Saturday night. Police detained more than 200 after they clashed with officers.
The decision to delay imports came after the ruling Grand National Party urged the government to take steps to restore public confidence, Yonhap said.
The party had been working to soothe tensions, saying that American beef is safe to eat and that adequate safety precautions have been taken.
In 2003, the United States exported beef and beef variety meats worth $815 million to South Korea. The U.S. beef industry has lost up to $4 billion since the market closed, according to the U.S. Meat Export Federation.