Transcript for Trump under fire for venomous tweets aimed at the hosts of MSNBC's 'Morning Joe'
And good evening. I'm Tom llamas in for David, and we begin with president trump facing the collapse of health care negotiations and the north Korean nuclear threat. Tonight, INT stead, striking condemnation about a cable host of a cable TV news show. The "Morning show" host, Mika Brzezinski, talking about having graphic reference to a facelift. Tonight, the white house defending the tweet saying the American people elected a president who fights fire with fire. Here's ABC's chief white house correspondent, Jonathan Karl. Reporter: Tonight, Donald Trump being presidential, welcoming the president of the South Korea to the white house. But earlier today, Donald Trump being anything but presidential. Launching a harsh personal attack on MSNBC television host Mika Brzezinski, calling her "Low iq crazy Mika." Saying that she and co-host and fiance Joe Scarborough came to visit him in mar-a-lago in December and quote, she was bleeding badly from a facelift. I said, no. The Twitter outburst came after Brzezinski criticized the president on her show this morning. Nothing makes a man feel better than making a fake cover of a magazine about himself, lying every day and destroying the country. Reporter: The president's tweets touched off an avalanche of bi-partisan condemnation. I think it's so blatantly sexist, I don't think there is any question about it. Obviously I don't see that as an appropriate comment. I think -- look, what we're trying to do around here is improve the tone and the civility of the debate. And this obviously doesn't help us do that. Reporter: Among the Republicans condemning the president, the two senators who were seated right next to him on a meeting on health care this week, because he needs their votes. Susan Collins. It clearly was inappropriate, and not something that he should have done. It is beneath the dignity of the office. Reporter: And fellow Republican Lisa murkowski, who tweeted, stop it. The presidential platform should be used for more than bringing people down. The white house press briefing was almost entirely consumed with questions about the the president's tweets. The president has been attacked mercilessly on personal accounts by members on that program. I don't think that it's a surprise to anybody that he fights fire with fire. Reporter: The episode which seemed to put first lady Melania trump in an awkward position. Before the election, she had said she would make combatting cyberbullying a cause as first lady. Have you thought more about what you would like to do as first lady? I will focus on helping children and women and also about helping social media in this 21st century. What is going on, it's very hurtful to children. To some adults as well. Reporter: Melania trump before the election. Jon Karl joins us now, and Jon, any response from the first lady to the it president's tweets? Reporter: We asked the first lady directly about this shortly after the tweets went out. What we got from her office was this statement. As the first lady as stated publicly when her husband gets attacked, he will punch back ten times harder. So no indication she considers this an example of cyberbullying. Jon, the timing of all this couldn't be worse. The fire storm comes with Republicans struggling to cut a deal on health care. Reporter: And the Republicans had hoped to have a deal by tomorrow. The vice president was on capitol hill today meeting with Republican senators, but Tom, as of this moment, there is no indication whatsoever of any further progress that they are any closer to getting a health care bill that will pass the senate. Jonathan Karl for us. Jonathan, thank you.
This transcript has been automatically generated and may not be 100% accurate.