He said the US had made "zero concessions" and "consistently increased the pressure" on North Korean leader Kim Jong-un.
An unprecedented summit between the two leaders is due to take place by May.
It comes only months after the pair hurled insults at each other.
In recent months, Mr Trump has belittled Mr Kim as the "rocket man", threatening him with "fire and fury", while Mr Kim has called Mr Trump "a mentally deranged US dotard".
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