The United States expressed great concern that North Korea is continuing its nuclear activities and pressured it to maintain sanctions against North Korea for denuclearization.

It also urged North Korea to return to the denuclearization negotiations table, discussing the possibility of North Korea having unidentified nuclear facilities and the possibility of establishing additional nuclear test sites.

The State Department said on the 23rd (local time) that it assessed North Korea's nuclear activities over the past year in the '2020 Arms Control, Non-Proliferation, Disarmament Agreement and Commitment and Implementation Report'.

The State Department said in a report that "throughout 2019, the United States continues to have great concerns about North Korea's nuclear weapons program and continued nuclear production."

He cites a report by the International Atomic Energy Agency (IAEA) in August last year that there were indications of centrifugal uranium enrichment facilities in North Korea's Yongbyon nuclear fuel rod manufacturing plant, including cooler operation and vehicle movement.

This report contained North Korea's nuclear activities in 2018.

The State Department cited the IAEA report that there were signs that the 5 megawatt (MW) plutonium production reactor at the Yongbyon Nuclear Research Center was operational by August 2018.

In addition, after the construction of an experimental light reactor in Yongbyon, the IAEA had not observed any signs of nuclear reactor operation, but in March last year, it said there were signs of testing of cooling facility parts.

The State Department said the US believes there is a possibility that there will be additional unidentified nuclear facilities in North Korea after reporting the contents of the IAEA report that there are activities such as mining in areas announced as Pyongsan Uranium Mine and Uranium Plant.

The State Department said it could almost certainly return to its original condition in relation to North Korea's closure of the Punggye-ri nuclear test site in May last year, and that North Korea could possibly build another nuclear test site.

He also said that North Korea's failure to allow international inspections of the nuclear test site at Punggye-ri raised the question of whether to give up further nuclear tests.

The State Department said it had delivered to the North's counterparts that North America is ready to pursue both the promises of Singapore's first summit concurrently and concurrently in June 2018, even after the breakup of the Hanoi summit in February last year.

The US also emphasized the need for'constructive negotiations', saying that if North Korea fulfills its commitment to denuclearization, it is ready to seek ways to improve investment, infrastructure, and strengthen food security.

However, the State Department said the United States will remain united with the international community until the'final and fully verified denuclearization' (FFVD) is achieved, and the United Nations and US sanctions will remain in place and fully implemented.

"The United States continues to closely monitor North Korea's nuclear activities," said the State Department. "North Korea's FFVD is the top priority of the United States, and the United States is committed to continuing diplomatic negotiations with North Korea toward this goal."

In regard to North Korea's bioweapons capabilities, the State Department said, "The United States considers North Korea to have an aggressive bioweapons program." North Korea is said to have had bioweapons capabilities since at least the 1960s.

North Korea also estimated that it might have weaponized biological weapons for use, and said it would have the ability to produce sufficient amounts of biological material for military purposes at the request of the leader.

(yunhap news)