Kim Yo Jong, the powerful sister of North Korean leader Kim Jong Un, criticised the presence of a U.S. nuclear submarine in the South Korean port of Busan, state media KCNA said on Tuesday.
Kim called it a proof of U.S. ambition to "bring out its nuclear strategic assets, show off its strength and increase threats", according to KCNA.
The USS Vermont arrived at a naval base in Busan on Monday to resupply and allow crew members to rest, Yonhap news agency said citing South Korea's navy.
Kim's published remarks came after the foreign ministers of South Korea, the United States and Japan held a meeting on Monday on the sidelines of the U.N. General Assembly.
They expressed concerns about North Korea's recent revelation of its uranium enrichment facilities and continued "unlawful" military cooperation with Russia, and agreed to work toward realising a trilateral summit within this year, South Korea's foreign ministry said in a statement.
