A U.S. nuclear-powered guided-missile submarine arrived in South Korea on Friday for the first time in nearly six years, the Defense Ministry in Seoul said, in a dramatic show of force a day after North Korea sent two ballistic missiles into Japan’s exclusive economic zone (EEZ) in waters off Ishikawa Prefecture.

The 18,000-ton USS Michigan submarine, which can conduct strike missions using Tomahawk cruise missiles, docked at a naval base in Busan, the ministry said, fulfilling a pledge by the U.S. to enhance the "regular visibility" of strategic assets — some of the United States' most powerful weapons — on the Korean Peninsula.

The move was agreed to in the so-called Washington Declaration, which was signed by South Korean leader Yoon Suk-yeol and U.S. President Joe Biden during an April summit in the U.S. capital.