A new type of tactical guided missile is launched from the North Korean town of Hamju, South Hamgyong Province, last Thursday, in this photo released by the North's Korean Central News Television the following day. Yonhap

By Jung Da-min

North Korea's launching of two short-range ballistic missiles has increased tensions between the United States and North Korea, while the Joe Biden administration is in the final stages of reviewing its North Korea policy.

Pyongyang watchers said North Korea is likely to continue missile tests claiming they are for the country's self-defense.

On March 21, Pyongyang fired two cruise missiles and four days later fired the ballistic missiles. Following the latest launch, U.S. President Joe Biden said there would be "responses" if Pyongyang chooses to escalate tensions and Washington would "respond accordingly."

The hermit regime has since expressed "deep apprehension" over Washington's criticism of its missile tests, saying they were exercises of "self-defensive right" to deter military threats posed against the regime, issuing statements under names of high-ranking officials through its state-run Korean Central News Agency.

Some North Korea experts say the North could escalate tensions by conducting tests of other types of ballistic missiles including submarine-launched ballistic missiles (SLBMs), while others predict Pyongyang will still not cross the "red line" by testing weapons that could reach territories of the U.S. such as intercontinental ballistic missiles (ICBMs).

"There are two reasons behind North Korea's continuing missiles tests," said Moon Sung-mook, a senior researcher at the Korea Research Institute for National Strategy. "From North Korea's point of view, the Biden administration would stay firm with its stance that North Korea should give up its nuclear weapons and push ahead with the complete, verifiable and irreversible denuclearization (CVID) of the North, which it could never accept. Pyongyang is trying to gain an advantageous position in upcoming denuclearization negotiations with Washington by continuing weapons tests to escalate regional tensions, in a form of protest against the Biden administration's message to the reclusive regime."

Moon also said because North Korea's leader Kim Jong-un publicly vowed to complete the development of weapons including SLBMs during the eighth congress of the country's ruling Workers' Party of Korea in January, the regime would need to continue weapons tests for such internal military purposes aside from negotiations with the U.S.

But Cho Seong-ryoul, a senior adviser at the Institute for National Security Strategy, said North Korea would not cross the "red line" by testing weapons that could strike U.S. territories, as they are banned by United Nations Security Council resolutions and could bring additional sanctions to the regime, which is already suffering from the existing ones.

"But I believe North Korea would continue to conduct tests of short- or middle- range missiles as they claim they are for the regime's self-defensive rights," Cho said.

Meanwhile, U.S.-based North Korea monitoring website 38 North reported last Friday that recent commercial satellite imagery of the North's shipyard on its east coast indicated that the floating dry dock, normally moored at a nearby pier, has recently been repositioned along the construction hall's submarine-launch quay, suggesting it may be ready to launch a new ballistic missile submarine in the near future.