Barely 12 hours after a "breakthrough" report that North Korean leaders might be willing to shut down their nuclear program and surrender their existing nukes in exchange for assurances that the regime's safety would be guaranteed, the State Department announced that it would impose yet another round of economic sanctions on the North - its second batch of sanctions within the span of two weeks, per Reuters.

MORE: State Department says it imposes additional sanctions on North Korea over assassination pic.twitter.com/mMiHuIJyk8 — Reuters Top News (@Reuters) March 7, 2018

The sanctions are being levied because the US has obtained solid evidence that North Korean leader Kim Jong Un ordered the assassination of his older half-brother, Kim Jong Nam, who was murdered in 2017 at an airport in Kuala Lampur when two young female assassins exposed him to a nerve agent, the US has determined.

JUST IN: U.S. State Department says U.S. has determined that North Korean government used chemical warfare agent VX to assassinate half-brother of Kim Jong Un in Malaysia in 2017 pic.twitter.com/Mb5nOdyI6K — Reuters Top News (@Reuters) March 7, 2018

MORE: State Department says it imposes additional sanctions on North Korea over assassination pic.twitter.com/mMiHuIJyk8 — Reuters Top News (@Reuters) March 7, 2018

State Department spokesperson Healther Nauert made the announcement in a press release.

"The United States determined under the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991 (CBW Act) that the Government of North Korea used the chemical warfare agent VX to assassinate Kim Jong Nam, in the Kuala Lumpur airport," Nauert said on Tuesday. These sanctions are in addition to the existing sanctions against targeting unlawful North Korean activities. The sanctions took effect upon this determination in the federal register on March 5, 2018. The United State sstrongly condemns the use of chemical weapons in carrying out assassinations. This public display of contempt against universal norms of chemical weapons use further demonstrates the reckless nature of North Korea and underscores that we cannot tolerate a North Korean WMD program."

Pyongyang has repeatedly denied allegations that it was involved in the murder. Two of the assassins were caught by Malaysian police and convicted. When asked about the reports of a possible breakthrough in US-North Korea relations, President Trump sounded noncommital, repeatedly responding '"we'll see what happens."

Meanwhile, Vice President Mike Pence released a statement saying the US wouldn't back down from its demands that the Korean peninsula be denuclearized.

Whichever direction talks with North Korea go, we will be firm in our resolve. The United States and our allies remain committed to applying maximum pressure on the Kim regime to end their nuclear program. All options are on the table and our posture toward the regime will not change until we see credible, verifiable, and concrete steps toward denuclearization.

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