The United States on Monday rejected a reported proposal by China and Russia to lift some United Nations sanctions on North Korea, saying it's "premature" to consider the move.

A U.S. State Department official made the comment after Reuters reported that China and Russia proposed a draft UN resolution that would lift some North Korea sanctions.

The official said that now is not the time for the UN Security Council to consider "premature sanctions relief."

The official reportedly said that North Korea is threatening to conduct an "escalated provocation" and refusing to meet to discuss denuclearization while continuing to maintain and advance its illicit weapons of mass destruction and ballistic missile programs. 

The official said that U.S. President Donald Trump remains committed to making progress toward the Singapore summit commitments of transformed relations, building lasting peace and complete denuclearization.

The official added that the U.S. remains committed to diplomacy to make progress towards those goals, but it cannot do this alone.