SEOUL - A senior official of the Democratic People's Republic of Korea (DPRK) on Tuesday condemned a port call by a US nuclear submarine to Busan, the Republic of Korea (ROK), vowing to boost the country's nuclear deterrent capabilities in response, the DPRK's state media reported.

Kim Yo-jong, vice-department director of the Central Committee of the Workers' Party of Korea, lambasted the United States for sending a newly commissioned nuclear submarine to the Busan operation base, calling the move an intentional display of "superiority of strength", said a press statement carried by the official Korean Central News Agency.

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Noting the security of the DPRK is constantly exposed to the US nuclear threat and blackmail, the statement stressed that the country will bolster its nuclear deterrence capabilities both in quality and quantity "continuously and limitlessly" to counter external threats.

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According to a report by Yonhap News Agency citing the ROK's Navy, the USS Vermont, a nuclear-powered and fast-attack submarine, arrived at the naval base in Busan on Monday to replenish supplies and provide a rest for its crew. It marks the first visit by the Virginia-class attack submarine to the ROK since its commission in 2020.