North Korea may be in the process of developing a 3,000-ton submarine that can provide a stable platform to launch three submarine-launched ballistic missiles as the country is scurrying to enhance its nuclear delivery capability, military experts here said Monday.

Local military observers said to meet such a goal, Pyongyang may move to test-fire SLBMs until it is confident in launching a missile that can fly as far as 2,000 kilometers, the experts also predicted.

On Saturday, North Korea fired a SLBM from a 2,000-ton Sinpo-class submarine in the East Sea in its latest SLBM test-firing after the country first publicized it carried out a SLBM ejection test in May 2015. 

After soaring from the water, the ballistic missile flew some 30 kilometers.

Although the flight distance fell far short of a regular SLBM that could fly several thousand kilometers, South Korean experts assessed that the North has made progress in advancing its technology from the initial ejection test stage to the flight test phase.

With the recent progress, North Korea may have already embarked on a project to build a larger submarine that could carry a number of SLBMs, an armament substantial enough to pose tangible threats to the United States, according to the experts. 

North Korea's current 2,000-ton submarine can embark and launch one SLBM from about 10 to 15 meters below the water's surface. This shallow depth puts the submarine at greater risk of detection compared with bigger SLBM-equipped submarines that could go down some 50 meters, the experts said. 

They also stressed that the communist country would continue to make efforts to increase its SLBM range to the extent that their submarine missiles could pose threats to the United States from very far away. 

"If the missile flew 30 kilometers in the initial flight test, it means progress has been made to some extent," one expert well versed on submarines said. (Yonhap)