South Korea hit back at North Korea on Monday over its direct criticism of President Park Geun-hye with the two sides locked in a war of words.

In a statement, the unification ministry said it's "very regrettable" that the North's National Defense Commission denounced Park by name over the weekend.

The commission, chaired by Kim Jong-un, said Park is fully responsible for the icy inter-Korean ties and Pyongyang will never talk with Seoul unless it averts its "confrontational" policy.

The commission was taking issue with the president's call for the North to admit to its culpability in the 2010 deadly torpedo attack on a South Korean warship.

"(The government) makes it clear again that there should be a responsible measure by North Korea in order to resolve the problem of the May 24th Measure intended to hold it responsible for the attack," the unification ministry's spokesman Lim Byeong-cheol said at a press briefing. He was referring to a package of bilateral sanctions on Pyongyang.

He also dismissed Pyongyang's claim that Seoul is cooking up a story on wartime abductees.

Many South Korean nationals were forcibly taken to the communist nation during the 1950-53 Korean War, and some of them are believed to be still alive there, according to the South's government.

The North said the South's view is groundless and it is making false reports for propaganda purposes.

Lim said his government will continue efforts to confirm the fate of the abductees and get them repatriated.

"We urge North Korea to respond positively to our humanitarian demand (with regard to the abductee issue)," he said.

Earlier Monday, North Korea played down South Korea's decision to join a China-led regional bank as a trade-off for the deployment of an advanced U.S. missile defense system on its soil.

On its propaganda website, Uriminzokkiri, the North claimed the U.S. will take a full-fledged step to send a Terminal High Altitude Area Defense (THAAD) battery to the peninsula as quid pro quo for allowing Seoul to become a member of the Asian Infrastructure Investment Bank (AIIB).

After months of internal debate, the South's government announced its decision last week to participate in the envisioned AIIB, which Washington apparently views as part of Beijing's efforts to expand its influence.

On its part, the U.S. is considering deploying the THAAD system in South Korea, citing growing military threats from the nuclear-armed North.

Chinese officials believe Washington is actually seeking to curb Beijing's clout.

The AIIB and THAAD issues represent a grim reality facing South Korea, sandwiched between its top ally and major economic partner next door.

The North said the U.S. is ratcheting up pressure on Seoul for the deployment of THAAD after letting it join the AIIB.

If THAAD is deployed on the peninsula, it added, the South and the U.S. will face serious consequences of war risks and an arms race. (Yonhap)