Transcript for US diplomats in North Korea for summit negotiations

Now to high-stakes fort to salvage president trump's summit with Kim Jong-un. He canceled it last week but now E administration says a tm of diploma crossed intoorth Korea Sunday to talk about terms. ABC's Bob woodrus on the story from beijing. Repr:st the summit was on,n it was off and now it C be back on. A delegation of U.S officials crossed into nor korea.president trump's effort to Sae his abruptly led summit wh Kim Jong-un. Thveg less than 2 hours after news a surprise meeting Een Kim Jong-un and south Korean president moon jae-in where Ty exchanged handshakes and even H and trump confirmed this trip iso make arrangements for the president meet with theorth Korean dictator tweeting, I truly believe North Korea H brilliant poten and will be a great ecoc and financial nation one Kim Jong-un agrees with M on this. Itl happen at the white house this weekend, the president opttic that the meeting cld go on as originally planned. So we're looking at June 12th in Singapore. That hasn't changed. Reporter: A remarkable of events after north last week threatened a nuclear-to-nuclear showdown. I have ded to terminate. Reporter: And the president suddenly called ohe summit. Even after in a gesture of goodwill north kor set a barrage of explosions right before visiting for journalists claing to destroy his nuclear test site but many includingator Marco Rubio remain skeptical. It's all a show. Eporter: There are reports sout Korea's president moon jae-in may soon it Singapore but not yet decide it is the U.S. And North Korea, two countries still officiay at war. Dan. Bob, thank you. Let's bring in Jon Karl. Jon, good morning. How does it look from your perch? What are the odds I happens? Reporter: Mykets are booked but most importantly there ar two U.S. Delegations now out in the field working on the one Bob reported on meeting wit the north Koreans nor Korea trying to see wh they're willing to agree on. There's also another U.S. Delegation right now in Singapore working on the logistics of the summito it looks like allystems go for this right N but this is art of the deal 101. To make a de youeed to be lling to walk aw. So, ther still the possibly that this thing goes offhe rails again. Buts Y said your tts are booked. LE ask Y about something else thiorning involving the Russia investigation. The president's attorney, Rudy Giuliani, was O television yesterday. He M some revealing moments. Tell us WHA you noticed. Rr: We Giuliani was quite clear that what they are trying to do is mine the credy of the Russia investigation. He was asked about thespygate charges and what he's trying to do and H simply trying to destroy the reputatio of T special counsel andhis is what he had to say. It is for public opinion. Members of congress, docrat and republic, will be informed a lot by tir constituents so our jury is -- as it should be, is the American people. Reporter:te explicitly what hs say is that they E trying to undermine Mueller's credibility so when you hear th spygate cha know, first of all, there is no evidce and, secondly, that re trying to wage pub relations gn re. Jon Karl at the white house, K you very much.

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