North Korea’s latest firing of a submarine-launched ballistic missile (SLBM) indicates that Pyongyang’s military threat is growing further. The international community must work together to speed up efforts to halt the country’s provocations.

The U.N. Security Council has started considering issuing a statement to condemn North Korea’s SLBM test launch toward the Sea of Japan. It is vital for the UNSC to swiftly send a strong message to North Korea, which has repeatedly conducted nuclear tests and ballistic missile launches in violation of U.N. sanctions resolutions.

The regime of North Korean leader Kim Jong Un opposes the planned deployment of the United States’ state-of-the-art Terminal High Altitude Area Defense (THAAD) missile system in South Korea. The SLBM launch, which was conducted during a U.S.-South Korean joint military exercise, was apparently intended to shake Japan, the United States and South Korea by demonstrating North Korea’s ability to carry out a surprise attack.

Kim, chairman of the Workers’ Party of Korea, watched the test-firing and declared that the SLBM launch proved his country “joined the front rank of military powers fully equipped with nuclear attack capabilities,” according to the Korean Central News Agency. He also ordered increased efforts to develop nuclear weapons and ways to deliver them, the KCNA reported.

If North Korea successfully deploys an SLBM equipped with a miniaturized nuclear warhead for combat use, it would allow the country to conduct nuclear attacks in various different ways. This is a source of grave concern that could undermine regional stability.

Signs of an impending SLBM firing are difficult to detect. Even if North Korean military forces on land were destroyed, SLBMs could enable the country to retaliate from a submarine.

Since North Korea test-fired the missile in waters in spring last year, its SLBM capability has improved significantly.