Iran Press/Asia:Officials in Pyongyang sent a letter declaring the negotiations were "again at stake and may fall apart”.
The letter was delivered directly to US Secretary of State Mike Pompeo and said North Korean leader Kim Jong-un's government now felt plans to disarm could not move forward.
It said: "The US is still not ready to meet North Korean expectations in terms of taking a step forward to sign a peace treaty.”
Donald Trump called off a visit to North Korea by Pompeo after he received a belligerent letter from the former head of North Korea's spy agency, Kim Yong Chol, just hours after the trip was announced.
It led Trump to acknowledge for the first time his efforts to get North Korea to denuclearise had stalled since his historic June 12 summit with Kim.
US intelligence and defence officials have repeatedly voiced concerns over North Korea's willingness to give up its nuclear weapons and had not expected Mr Pompeo's trip to yield positive results.
CNN reported the letter also mentioned that if a compromise could not be reached and the talks failed, North Korea could resume "nuclear and missile activities".
North Korean state media went on to accuse Washington of "double-dealing" and "hatching a criminal plot" but did not mention the cancelled visit.
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