The Japanese prime minister on Thursday warned that its bellicose rival, North Korea, may have the technology to launch missiles with sarin nerve gas, Reuters reported.

Shinzo Abe, the prime minister, made the comment during a parliamentary session.

The New York Times described sarin gas as an agent that disrupts nerve signals sent to vital organs. It was developed in secrecy during WWII and a whiff of vapors or any exposure to the skin “can quickly become a death warrant.”

North Korea appears to be taking an aggressive posture after the U.S. bombed Syria last week. North Korea vowed tough counteraction to any military moves that might follow the U.S. move to send the USS Carl Vinson aircraft carrier and its battle group to waters off the Korean Peninsula.

The statement from Pyongyang comes as tensions on the divided peninsula are high because of U.S.-South Korea wargames now underway and recent ballistic missile launches by the North. Pyongyang sees the annual maneuvers as a dress rehearsal for invasion, while the North's missile launches violate U.N. resolutions.

Satellite imagery shows activity at the Punggye-ri testing site, analysts from 38 North, a U.S. research institute that monitors North Korea, wrote on its website Wednesday. Foreign journalists inside the country were told to prepare for a "big and important event" Thursday, Reuters reported.

Chinese President Xi Jingping told Trump in a phone call Wednesday that he wants a peaceful solution to ending North Korea’s nuclear weapons program and would be willing to work with Washington on the matter.

"China insists on realizing the denuclearization of the peninsula ... and is willing to maintain communication and coordination with the American side over the issue on the peninsula," Xi was quoted as saying by state media.