U.S. Army Chief of Staff General Martin Dempsey made an unofficial two-day trip to South Korea this week.

A Joint Chiefs of Staff official in Seoul says that Dempsey arrived in Korea Thursday, and on Friday met with South Korean JCS Chairman Han Min-koo at the Defense Ministry for about an hour.

The two are believed to have discussed North Korea's nuclear arms development and preparations it is making to conduct missile tests.

The official says Dempsey likely visited South Korea to familiarize himself with the U.S. ally's military issues ahead of his Senate confirmation hearing to become the chairman U.S. Joint Chiefs of Staff.

He was nominated to the post in May and is expected to take office in October following the Senate hearing.