Envoy to North Korea accused the country of becoming "more aggressive" in its weapons tests

The US has agreed to collaborate with Japan and South Korea on future sanctions on Pyongyang, a senior South Korean official has said. The statement comes after the US State Department declared that Washington "won't hesitate" to blacklist anyone found aiding North Korea's missile or nuclear programs.

Speaking after a trilateral summit with his American and Japanese counterparts at the US Embassy in Indonesia on Tuesday, Seoul's envoy for peace and security affairs on the Korean Peninsula, Kim Gunn, said the three allies would work closer while devising new penalties for the North.

"South Korea, Japan, and the United States will coordinate sanctions and close gaps in the international sanctions regime against North Korea," the official said, as cited by Reuters, adding that Pyongyang is "becoming more aggressive and blatant in its nuclear threat."

Kim met with Washington's North Korea envoy, Sung Kim, as well as senior Japanese Foreign Ministry official Takehiro Funakoshi, and discussed "regional security," ways to bring Pyongyang back to the negotiating table, and how to respond to a future nuclear test by the North, according to Yonhap.

The envoy's comments came just hours after US State Department spokesman Ned Price told reporters that the US is "always looking for individuals who would be appropriate to sanction" for assisting North Korea's nuclear weapons or ballistic missile programs, adding "we won't hesitate to do that."

North Korea has carried out a record number of weapons tests this year, many in direct retaliation to joint US-South Korean military drills which the DPRK has repeatedly denounced as practice for an invasion. Nonetheless, Washington, Seoul, and Tokyo alike have sounded alarms over the North's missile launches, claiming they undermine regional stability and increase the chances for conflict on the Korean Peninsula. 

On Monday, South Korean Prime Minister Han Duck-soo alleged that North Korea is preparing for another nuclear test, echoing similar warnings from US officials in recent months. Though Han acknowledged he could not say "exactly when" the test would be carried out, both the US and South Korea have vowed a stern response should the North go through with a nuclear detonation, which would mark the country's seventh test since its first successful trial in 2006.

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