The United States is stepping up pressure on South Korea to improve access to its auto markets.

The Senate and the House are to adopt a resolution calling for South Korea to open its markets to U.S. auto imports.

The U.S. auto manufacturers complain that South Korea's auto markets are too restricted in allowing foreign imports. They claim that South Korea shipped more than 500-thousand units to the U.S. markets last year, but the U.S. sold only one thousand 200 units.

South Korea is denying the charges, saying that the sluggish U.S. auto sales is not because Korean markets are closed, but because U.S. automobiles are not price competitive.