The United States expressed concerns over North Korea's continued production of fissile materials, vowing to maintain sanctions until the North completes a final, fully verified denuclearization.

This is according to the State Department's report on arms control and nonproliferation released on Monday.

The department was concerned about construction of an experimental light water reactor(ELWR) under way at the North's Yongbyon nuclear facility, which could be used to secure the uranium enrichment technology required to make fissile material and arm nuclear weapons.

The report said Pyongyang's continued nuclear activity is a clear display of its violation of denuclearization agreements with Washington at their historic summit in Singapore in 2018.

While the U.S. is prepared for constructive dialogue with the North in achieving the ultimate goal of denuclearization, the report said sanctions imposed by the U.S. and the United Nations will remain in place until they reach their objectives.
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