South Korea strongly condemned North Korea for its test of another submarine-launched ballistic missile (SLBM) on Sunday, vowing to take "necessary steps" including those at the U.N. Security Council (UNSC) in tandem with the international community.

The North's state media claimed that it successfully conducted an SLBM launch in the East Sea with its leader Kim Jong-un observing the test. Seoul's Joint Chiefs of Staff said the test might have been a failure given that it only traveled 30 kilometers.

"We will take necessary steps in close cooperation with related countries," Foreign Ministry spokesman Cho June-hyuck said in a commentary. "Regardless of whether the test was a success or not, it is a clear violation of UNSC resolutions."

Calling the latest "open" provocation a serious threat to regional and world peace, Cho pointed out that the SLBM test came less than 10 days after the UNSC upbraided Pyongyang for its failed intermediate-range missile test through a press statement.

"The government has warned on various occasions that the North would face stronger and more stern responses from the international community in the event of its additional provocation," he said.

"We will further strengthen our efforts to increase pressure on the North through the faithful implementation of the UNSC sanctions resolution and international cooperation."

Cho's warning appears intended to prevent Pyongyang from undertaking yet another underground nuclear test. Recent satellite imagery indicated a sharp rise in the movement of workers, vehicles and equipment in the Punggye-ri nuclear test site in the country's northeast. (Yonhap)