Transcript for Defense secretary says 'possibly some good news' on Korean summit

Next tonight, the political headline. The nortkorea summit guessing game. The white house now indicating the on again/off again talks between president trump and Kim Jong-un may take place next month after all. 24 hours after calling the canceled meeting a tremendous setback and threatening military action, president trump now says the Singapore summit could still happen on June 12th. Here's ABC's chief white hse correspond, Jonathan Karl with new reporting. Reporter: A day after abruptly canceling his summit with Kim Jong-un, the president suggested it could happen after all. We'll see what happens. It could even be the 12th. We're talking to them now. They very much want to do it. We would like to do it. We'll see what happens. Reporter: An about face from the north Koreans. A quote/unquote nuclear-to-nuclear showdown, and saying they are willing to meet with the U.S., , quote, any time wit a generous and open heart. Areou concerned that north Koreans could be trying to play games here not showing up at the various meetings. Jon, everybody plays games. You know that. You know that better than anybody. Reporter: It was north Korea's hostile statements that prompted the president's letter to Kim Jong-un, pulling out of the summit, citinghe north's tremendous anger and open hostility. But for now at least, that aggression seems to have evaporated. Prompting even the defense secretary to say diplomacy may yet save the summit. We've got possibly some good news on the Korea summit. Diplomacy could pull it off, and maybe have it back on even. Reporter: One oer possible development, in a series of explosions sterday, north Korea claimed to destroy its nuclear testing facility before an audience of foreign journalists. Today, the president gave a commencement address at the naval academy. Heade no mention of north Korea, but he did tell the aduates this. And if a fight must come, there is no other alternative, victory, winning, beautiful words. But that's what it's all about. All right. Jon joins us now from the white house, and Jon, it was just last night when the white house officials TD you there was no way this summit would happen as plned, but that's not what your sources are saying tonight? Reporter: Tonight, the line is anything is possible. In fact, planning for a possible summit continues, and a delegati here from the white house is schedule to go to Singapore this weekend to work out logistics just in case the summit gets back on track. Yesterday we were told that won't happen. Today, officials are saying, well, it just might. Tom? That whiplash continues. Jonathan Karl with that new reporting. Dhaung. On this memorial day weebd,

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