The North appears to have also restarted operation of a reactor at its main Yongbyon nuclear facility that produces plutonium that can be used for its nuclear weapons program, according to US think tank 38 North.
“North Korea continues to launch missiles, develop its nuclear weapons program and engage in threatening rhetoric and behavior,” Mattis said.
North Korea’s actions have prompted the United States and South Korea to respond by bolstering defenses, including the expected deployment of a US missile defense system, known as Terminal High Altitude Area Defense (THAAD), in South Korea later this year.
China, however, has objected to THAAD, saying it will destabilize the regional security balance, leading to calls from some South Korean opposition leaders to delay or cancel it.
South Korean Defence Minister Han Min-koo reaffirmed plans to deploy THAAD and said Mattis’ visit to Seoul – his first trip abroad as defense secretary – sent a clear message of strong US support.
“Faced with a current severe security situation, Secretary Mattis’ visit to Korea … also communicates the strongest warning to North Korea,” Han said.
