President Lee Myung-bak says the government will secure a firm guarantee from the U.S. that it’ll ban American exporters from selling Korea beef from cattle older than 30 months.

In a special news conference Thursday, Lee said the government will not post new beef import rules without that guarantee.

The president also said he believes Washington will understand and accept Seoul’s request, stressing many times that the two sides are negotiating the matter.

Mr. Lee said he’d conveyed such positions and requests to U.S. President George W. Bush in recent telephone talks. Bush reportedly told Lee he understands the situation and promised his cooperation.