South Korea urged North Korea on Saturday to abandon its “delusion” that nuclear weapons will protect its regime as Pyongyang bristled at new U.N. sanctions on the country.

On Friday, the North threatened to take “strong and merciless actions” in protest of the U.N. Security Council adopting unprecedentedly tough sanctions over the country‘s nuclear and long-range rocket tests earlier this year.

It rejected the sanctions as “the most reckless provocation”

and vowed to take “stern” actions.

“Our government, in response to such reckless behavior by North Korea, will make it wake up from its delusion about nuclear development through strong and effective measures,” Seoul’s Foreign Ministry said in a statement. “Our government has already stated that we will no longer tolerate the exploitation of the North Korean people, and the extreme and cruel reign of terror used to maintain the Kim Jong-un regime.”

The ministry said North Korea‘s threat amounts to a “flagrant challenge” to the international community’s resolve expressed in the unanimous adoption of the UNSC resolution on Wednesday.

South Korea will strengthen its defense posture and closely cooperate with the international community to respond to the North‘s provocations and resistance, it added.

The U.N. sanctions call for mandatory inspection of all cargo going into and out of North Korea and a ban on the country’s exports of iron and other mineral resources, among other things.

The measures were punishment for North Korea‘s fourth nuclear test on Jan. 6 and long-range rocket launch on Feb. 7, both of which violated past U.N. resolutions.

Angered by the fresh sanctions, North Korean leader Kim Jong-un on Thursday ordered the country’s nuclear arsenal on standby.

“We hope North Korea will abandon its nuclear weapons development, choose the path of peace wished for by the U.N. and the international community, and wake up from the delusion that nuclear weapons will protect its regime, and we once again strongly urge it to choose the path of sincere change toward denuclearization,” the ministry said. (Yonhap)