"We have made clear we have no hostile intent toward the DPRK and seek serious and sustained diplomacy to address the full range of issues of concern to both countries and the region," said a spokesperson for the White House National Security Council.

On Tuesday Austin and his South Korean counterpart vowed to expand military drills and deploy more "strategic assets," such as aircraft carriers and long-range bombers, to counter North Korea's weapons development and prevent a war.

North Korea will respond to any military moves by the United States, and has strong counteraction strategies, including "the most overwhelming nuclear force" if necessary, the statement added.

Last year, North Korea conducted a record number of ballistic missile tests, which are banned by United Nations Security Council resolutions.

Guterres said any resumption of nuclear testing by North Korea would deal a devastating blow to regional and international security, and reaffirmed support to build lasting peace on the Korean peninsula, according to Park's office.

"The combined air drills this time show the U.S.' will and capabilities to provide strong and credible extended deterrence against North Korea's nuclear and missile threats," the Defense Ministry said in a statement.