The addition of long-range missile tests to the negotiations was new.
«The US was not ready to accept our proposal,» Ri told reporters.
He said the US had demanded «one more» measure beyond Yongbyon that North Korea was not willing to accept.
North Korea’s offer will not change even if the US seeks further talks, he said.
Elsewhere, South Korean media reported on Thursday evening the former South Korean unification minister Jeong Se-hyun had blamed US national security adviser John Bolton for derailing the summit by demanding North Korea disclose their chemical and biological weapons.
Ri said Kim Jong-un may have lost the will for further talks. «Chairman Kim got the feeling that he didn’t understand the way Americans calculate,» he said.
Chairman Kim got the feeling that he didn’t understand the way Americans calculate.
Ri Jong-ho, North Korea foreign minister
North Korea had sought the lifting of sanctions that were damaging the livelihood of North Korean people, he said.
By contrast, Trump had told reporters at a press conference earlier in Hanoi that a working lunch and signing ceremony had been cancelled because North Korea wanted sanctions lifted in their entirety.
US secretary of state Mike Pompeo had said: «We asked him to do more and he was just unprepared to do that.»
On Thursday morning, ahead of the meetings, Kim had told reporters he would not have come to Hanoi if he wasn’t serious about denuclearisation.
«If I had no such will, I wouldn’t have come here,» he said.
Kirsty Needham is China Correspondent for The Sydney Morning Herald and The Age.