The proposed steel duty is the latest in a series of import restrictions by the Trump administration, including safeguard duties on Korean washers and solar panels imposed earlier this year.

The business group said South Korea should be an exception to the universal steel tariffs because it is Washington's longstanding ally, which signed a mutual defense treaty in 1953. The two nations are expected to resume their annual military drills against North Korean provocations later this month.

It also stressed the close economic ties between Seoul and Washington after implementing a free trade agreement in December 2012, which greatly boosted bilateral trade.

While major US trade partners like Canada, China and the European Union have threatened to take retaliatory actions, the Korean government has remained cautious over its next move amid ongoing negotiations to amend the FTA with the world's largest economy.

Korean Trade Minister Kim Hyun-chong has been in Washington since Feb. 25 to meet with senior American officials, including US Trade Representative Robert Lighthizer, as part of outreach efforts to help ease toughening import restrictions on South Korean goods.

South Korea shipped 3.6 million tons of steel products to the US last year, becoming the No. 3 steel exporter after Canada and Brazil, according to the US Department of Commerce.

Industry officials say the new duties, in addition to the incumbent heavy tariffs, will sharply raise prices of South Korean exports, hurting their price competitiveness against American manufacturers. (Yonhap)