North Korea said on Thursday it had successfully test-fired a new submarine-launched ballistic missile the day before to contain external threats and bolster its defenses ahead of fresh nuclear talks with the United States.

The launch was the most provocative since North Korea resumed dialogue with the U.S. in 2018, analysts said, and was a reminder by Pyongyang of the weapons capability it has been aggressively developing, including intercontinental ballistic missiles.

North Korean leader Kim Jong Un "sent warm congratulations" to the defense scientists who conducted the test, state news agency KCNA said, indicating he did not attend the launch, unlike previous tests of new weapons systems.