The Associated Press (AP) says progress in efforts to conclude a South Korea-U.S. free trade agreement has been slowed by U.S. demands that South Korea reduce its surplus in auto trade and further open its market to American beef.

The report said Thursday that South Korea eventually agreed to resume imports of U.S. beef after they were halted when a Canadian-born cow infected with mad cow disease was discovered in the U.S. in 2003.

The report said, however, that huge street demonstrations in South Korea that followed forced the government to backtrack and limit shipments to younger cows considered less at risk. The report said that the U.S. has repeatedly stated that its beef is safe.

The report said the leaders of South Korea and the U.S. have suffered a sharp setback to hopes of speedily ratifying the trade accord due to the delay.