The two short-range projectiles North Korea fired into the East Sea on Sunday were super-large rockets, the North’s Korean Central News Agency said Monday, calling the test a “success." Unlike previous launches, leader Kim Jong-un was reportedly not there to guide the latest test.

This was the North’s fourth weapons test this year, all in March. Pyongyang tested super-large rockets March 2 and 9 and ballistic missiles March 21 in an unprecedented flurry of launches that South Korea all denounced as an “inappropriate” military act.

The US urged the North to resume nuclear talks that have been deadlocked since their working-level talks fell apart in October. Both countries had since failed to work out their differences over Washington’s demand for disarmament and Pyongyang’s insistence on sanctions relief.

“We continue to call on North Korea to avoid provocations, abide by obligations under UN Security Council Resolutions and return to sustained and substantive negotiations to do its part to achieve complete denuclearization,” US State Department officials told Voice of America.

Experts warned that Pyongyang was speeding up the combat readiness of its four sets of short-range weapons -- missiles and rockets -- demonstrated the previous year. Some of them were already put into combat operation, according to Kim Dong-yub, an analyst from Seoul’s Institute for Far Eastern Studies.

“What’s alarming is the longer range, lower altitude, faster travel speed and increasing accuracy of those weapons that now fire consecutively, presumably quicker than before. They could penetrate our anti-missile shield,” Kim said

But those weapons were tactical at best, so leader Kim Jong-un would guide a strategic weapon test later, as he had openly vowed to do so at his key party in January, according to Kim, who added Kim Jong-un could test a submarine-launched ballistic missile or reveal a new intercontinental ballistic missile.

But, he dismissed an engine test involving an ICBM as a “hard choice” for leader Kim, saying that would scuttle nuclear talks and invite harsher sanctions.

“Kim Jong-un is sticking to the hard-line policy he laid out in December,” Ankit Panda, a senior fellow at the Washington-based Federation of American Scientists, told Reuters.

By Choi Si-young (siyoungchoi@heraldcorp.com)