North Korea's continuing development and test-launch of submarine-launched ballistic missiles constitute a violation of United Nations resolutions, the Defense Ministry said Monday, following the North's reported SLBM launch over the weekend.

A South Korean government official said North Korea fired a KN-11 missile from a submarine in the East Sea on Saturday afternoon, but the SLBM failed to leave the water. 

The remarks indicate the country has yet to master the SLBM technology since its first test in May.

"Under U.N. resolutions, North Korea is prohibited from developing or testing any kind of ballistic missile," Defense Ministry spokesman Kim Min-seok said in a regular briefing. "It practically constitutes a U.N. resolution violation," Kim said.

The spokesman, however, refused to discuss the details of the launch and did not directly confirm the test, saying "all the details related to North Korea's SLBM launch is confidential."

"At any rate, North Korea is continuing its development experiment for SLBM and South Korean and United States authorities are keeping a close eye on the process," he said. (Yonhap)