The U.S. has welcomed South Korea's decision to join international sanctions on Russia in response to its invasion of Ukraine.

Department of Defense spokesperson John Kirby said Friday in a press briefing that the U.S. welcomes comments made by South Korea and its willingness to impose sanctions on Russia as so many other countries are doing.

Kirby said countries are making very clear their condemnation of the invasion, and again welcomed South Korea's contributions to that effort.

He said the clear message from the international community is that Russian President Vladimir Putin continues to isolate himself and his people by these "reckless and unlawful" actions.

On whether to request Seoul's support over the Ukraine crisis, Kirby had said in January that it is up to the Korean government but that Ukraine would welcome its support.

President Moon Jae-in said Thursday the use of armed force that claims innocent lives cannot be justified under any circumstance and expressed the will to join global sanctions against Russia. 

However, Seoul's foreign ministry said it is not considering separate, unilateral sanctions.