Japan’s top government spokesman said on Wednesday that it is “extremely important” that North Korea show its commitment and concrete actions toward abandonment of its nuclear missile development in a complete, verifiable and irreversible way.

Chief Cabinet Secretary Yoshihide Suga told a news conference that it was necessary to respond to North Korea’s possible offer of dialogue based on the lesson from past talks that did not lead to denuclearization.

North Korea seems “sincere” in its apparent willingness to halt nuclear tests if it held denuclearization talks with the United States, President Donald Trump said on Tuesday as U.S., South Korean and Japanese officials voiced scepticism about any discussions.