North Korean leader Kim Jong-Un has accused the US of "acting in bad faith" at the Hanoi summit.
That's according to North Korean media, which said the leader warned that a state of hostility could easily return.
During his talks with Russian President Vladimir Putin in Vladivostok, Kim hinted that peace and security on the Korean peninsula depended entirely on Washington.
Kim has said he would wait until the end of the year for the US to be more flexible.