South Korea's finance minister has asked his U.S. counterpart for a tariff exemption on imported vehicles following the ratification of a revised bilateral trade pact.

Seoul's Finance Ministry said South Korean Finance Minister Hong Nam-ki and U.S. Treasury Secretary Steven Mnuchin spoke for about 20 minutes on the phone on Tuesday. They covered a wide range of bilateral issues including trade, foreign exchange policies and inter-Korean relations.

Minister Hong expressed concerns about potential tariffs on Korean automobiles based on Section 232 of the Trade Expansion Act on national security grounds, and asked Mnuchin's support for an exception.

Mnuchin reportedly said he will share Hong's concerns with the White House, Department of Commerce and the U.S. Trade Representative, and will try to get South Korea's voice heard on the matter.