SEOUL, South Korea (AP) _ South Korea's president called for an end to a festering dispute over American beef imports, saying Thursday it was time for the nation to concentrate on overcoming domestic and economic difficulties.

President Lee Myung-bak made the request in a nationally televised speech to cheering ruling party members who had packed a Seoul gymnasium to elect their new leaders.

``We are facing dual challenges at home and abroad,'' Lee said. ``Our law and order have been ignored and our economic difficulties have been deepened. We must wisely and squarely surmount these challenges.''

Lee said his government would make ``a fresh start'' to win back public confidence and that he was confidant of overcoming the difficulties in cooperation with Grand National Party members.

His speech was interrupted several times as party members applauded and shouted in unison, ``Lee Myung-bak! Lee Myung-bak!'' It was the first time the president has spoken to GNP members since his landslide election victory last December.

Later Thursday, the GNP elected Park Hee-tae, a five-time lawmaker and close associate of Lee, as its new chairman. Park said in a victory speech that his party will dedicate itself to reviving the slowing economy and restoring public support.

The president urged the GNP to unite in resolving the beef dispute _ which he believes scared off foreign investors _ and overcoming economic woes such as surging global oil prices.

``I received many telephone calls via hot lines (from foreign investors) about whether it will be OK to come to South Korea,'' Lee said at a trade fair Thursday. ``They are worrying much.''

Lee said he would not tolerate illegal, violent protests against U.S. beef imports, though he would listen more carefully to public opinions at peaceful rallies.

Lee's government agreed to lift a long-term ban on U.S. beef imports in April, prompting weeks of street rallies over health concerns and a perception that he had backed down too easily to American pressure. Amid nose-diving popularity, Lee was forced to replace top advisers and his entire Cabinet has offered to resign.

Seoul negotiated an amendment to the import deal last month to limit shipments to beef from cattle younger than 30 months, believed less susceptible to mad cow disease.

Daily candlelight protests in Seoul _ which had reached up to 80,000 people _ have dwindled in size but turned violent last week when the South Korean government began inspecting U.S. beef. More than 200 protesters and riot police were injured during a weekend rally.

U.S. beef went on sale earlier this week but is not widely available because large supermarket chains and restaurants are reluctant to sell it for fear of a public backlash. The sale was believed to be limited to only a handful of stores.

On Thursday, South Korean consumer groups launched a nationwide campaign to boycott U.S. beef, vowing to make the country free of mad cow disease.

``We will oust American beef feared to carry mad cow disease from our dinner tables without fail,'' the Korean Women's Association United and four other civic group coalitions said in a statement.

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