North Korean leader Kim Jong Un has reportedly announced the country will launch its "toughest" counteraction strategy toward the United States.

State-run Korean Central Television reported on Sunday that Kim made the remarks during an enlarged plenary meeting of the Central Committee of the ruling Workers' Party. It said the meeting was held in Pyongyang from Monday through Friday and that participants discussed policies for next year, as well as personnel plans.

Kim said in his speech that the United States is the "most reactionary" state, and that the US-Japan-South Korea alliance has expanded into what he called a nuclear military bloc for aggression. He added that South Korea has turned into an anti-communist outpost for the US.

It is unclear from the report whether Kim made any comment on the country's nuclear and missile development programs.

In a personnel reshuffle, the report said Pak Thae Song was appointed as new premier to replace Kim Tok Hun. Pak previously served as chair of the Supreme People's Assembly, among other posts.

South Korea's Yonhap News Agency says Pak has been among the top cadres seen alongside Kim Jong Un. It also says Pak currently chairs North Korea's space science and technology committee, which is involved in artificial satellite launches.