A South Korean national who has been sanctioned by the U.S. Department of Treasury for supporting Russia's military procurement efforts is under investigation locally for allegedly circumventing regulations on exports to Russia.

An official at the foreign ministry said on Wednesday that since the outbreak of the war in Ukraine, Seoul has introduced and enforced export controls and financial sanctions against Moscow as a responsible member of the international community.

The official added that Seoul plans to reinforce the effective enforcement of existing sanctions while closely coordinating with Washington.

On Tuesday, the Treasury Department's Office of Foreign Assets Control announced sanctions against 150 entities and individuals from various countries, including South Korean Lee Dong-jin.

The 61-year-old was described to have assisted in the fulfillment of Moscow-backed AK Microtech's orders for equipment and technology, including some critical in semiconductor production, from South Korean, Japanese and U.S. manufacturers.

The company was sanctioned by the U.S. in July.

Subjects to the sanctions are banned from visiting the U.S. and doing business with companies or individuals there, while their assets in the country are also subject to a freeze.