Transcript for Trump faces surprise resignation of UN ambassador

surprise resignation of U.N. Ambassador Nikki Haley. She's the 12th senior official to leave the administration this year. Speculation swirling about why the rising GOP star is making the move just weeks before midterm elections. Cecilia Vega has all the latest. Good morning, Cecilia. Reporter: Good morning to you. President trump says Haley told him she wanted off the job six months ago but this surprise announcement caught some top administration officials by surprise. President trump back on the campaign trail. This is truly a historic week for America. Reporter: Using his recent supreme court victory to rally supporters in Iowa and stoke anger at Democrats. What the Democrats did to Brett and his beautiful family is a national embarrassment, a national disgrace. Reporter: But that victory lap overshadowed by the latest shake-up back home. U.N. Ambassador Nikki Haley caught even some top administration officials off guard with her surprise resignation announcement. President trump says, no hard feelings. I think she's helped make it a much better position if you want to know the truth. I think it's become maybe a more glamorous position than it was two years ago. Reporter: She was also one of the few women in the president's cabinet. Someone who didn't hesitate to publicly disagree with him saying this about the women accusing the president of sexual misconduct. They should be heard and they should be dealt with. Reporter: As for why she's leaving now, Haley is not saying. There's no personal reasons. I think that it's just very important for government officials to understand when it's time to step aside. Reporter: The one thing she says not on the horizon. No, I am not running for 2020. I can promise you what I'll be doing is campaigning for this one. Reporter: She had a special message for two people who were right there in the room. Jared is such a hidden genius that no one understands. And ivanka has been just a great friend. Reporter: Now among the names being floated as a possible Haley replacement, Ivanka Trump. Ivanka would be dynamite. Is it a serious consideration? I think ivanka would be incredible. It doesn't mean I'd pick her because you'd be accused of nepotism. Even though I'm not sure there's anybody more confident in the world but that's okay. Reporter: And just like that Ivanka Trump took herself out of the running with a tweet saying, I am not that replacement so we can cross that name off the list. So she's off the list. Who is on it? Well, the president says he has a list of about five names long. We know among them is deputy -- former deputy national security director Dina Powell. One of the names on the list. The president says he wants to name this replacement over the next two to three weeks, George. That could make for a pretty long, awkward transition since Haley says she's not leaving until the end of the year. No confirmation till after the elections. Thanks very much.

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