SEOUL >> Impoverished North Korea could bring its own collapse if it keeps pouring scarce national resources into its nuclear weapons program and military, a senior South Korean official warned in an interview to be broadcast Monday.

South Korean officials have used tough language against North Korea after two deadly attacks last year killed dozens of people. But it’s still rare for a top Seoul official to speak publicly on a potential North Korean collapse and shows the South’s growing impatience with its communist neighbor.

“I think they will come to the point where they can no longer sustain the burden of military expenditure,” Chun Yung-woo told “PBS NewsHour,” according to part of the interview posted on the U.S. public broadcaster’s website.

Chun is South Korea’s chief presidential adviser on national security and foreign affairs and once was the South’s top negotiator on now-stalled six-nation talks on the North’s nuclear weapons program.

“They are already suffering from misery … I think they will be worse off,” Chun said. “I think their obsession with their military capabilities, especially weapons of mass destruction like nuclear weapons, chemical weapons … that would be a short-cut to their demise.”

He said “the energy for changing” North Korea is growing but declined to predict when that change may happen.

North Korea’s state-controlled economy was devastated by natural disasters and mismanagement in the 1990s, and a botched 2009 currency reform and massive flooding last year are feared to have worsened it. However, experts say the North still devotes much of its scarce resources to its 1.2 million-member military under its “army-first” policy.

In November, the North unveiled a uranium enrichment facility that could give it a second way to make atomic bombs in addition to its known plutonium-based program. The North has deployed new types of tanks near the border with South Korea and boosted its special operations forces in recent years, according to an official South Korean defense document released late last month.

Tension on the peninsula spiked after North Korea unleashed artillery shells on a front-line South Korean island near their disputed sea border, killing four people. The shelling came eight months after a deadly warship sinking that South Korea and the U.S. have blamed on Pyongyang. The North has denied its responsibility for the sinking that killed 46 sailors, and says the South provoked the island attack with nearby military drills.

Chun said the attacks indicate how desperate North Korea is due to its economic crisis.

“I think North Korea’s behavior enabled us to see North Korea as it is, not as we want to see it,” Chun said. “I am inclined to see it as an indication of their desperation.”