Transcript for Debate over 'zero-tolerance' policy intensifies

the president arriving on capitol hill late today, doubling down on his administration's own zero tolerance policy. But blaming the Democrats. The president hugging the American flag after an address to business leaders today. Will he agree to what Republican senators are now proposing late today? ABC's Cecilia Vega at the white house tonight. Reporter: Tonight, president trump arriving on capitol hill to meet with Republican lawmakers about the immigration crisis. Calling America's immigration system, probably the worst in the world. The system has been broken for many years, the immigration system, it's been a really bad, bad system, probably the worst anywhere in the world. And we're going to try to see if we can fix it. Reporter: With his white house engulfed in controversy, the president launching a forceful defense of his policy to separate migrant children from their parents. I don't want children taken away from parents, and when you prosecute the parents for coming in illegally, which should happen, you have to take the children away. Reporter: The president repeating the false claim that the law requires the separation. Even though there is no law. This is his policy. People that come into violate the law, they endanger their children in the process and frankly, they endanger all of our children. Reporter: And he is still falsely placing blame squarely on the Democrats, tweeting, "They want illegal immigrants, no matter how bad they may be, to pour in and infest our country." The images of those children in detention sparking outrage and moving one top Democrat to tears. Child internment camps, that's what I said. Child internment camps. What country is that? This is the United States of America. Reporter: Senator Bob Menendez playing sounds of their cries on the senate floor. Papa! Those are the cries of innocent children. Reporter: Outside of Dallas -- What are you doing? You're protecting trump! You're protecting trump. Reporter: The outrage taking over Republican congressman Michael burgess's town hall. I mean, I haven't been sleeping because of what's going on. Do you agree we need to take care of these children? We are taking care of those children. Your tax -- Reporter: Now on capitol hill, Republicans feeling the pressure to act. Lawmakers calling the policy "Cruel, tragic and an affront to the decency of American people." I support, and all of the members of the Republican conference support, a plan that keeps families together while their immigration status is determined. Reporter: The white house says he doesn't want a quick fix. He wants immigration reform and his wall. His own aides sending confusing and inaccurate messages about why the policy exists. Yesterday, homeland security secretary kirstjen Nielsen bristled when asked if the administration is using these children as pawns. Are you intending for parents to be separated from their children? Are you intending to send a message? I find that offensive. Why? No. Because why would I ever create a policy that would purposely does that? Perhaps as a deterrent. No. Reporter: But just hours later, from the attorney general -- Is it a deterrent, sir? Are you considering it a deterrent? Yes, hopefully people will get the message and come through the border at the port of entry, and not break across the border unlawfully. Sounds like a clear contradiction there. Cecilia Vega live from the white house. And Cecilia, the Republican majority leader, senator Mitch Mcconnell, saying today the senate could act this week now on a tightly focused bill that he says would keep families together, but obviously, the question tonight, would the president even go along with this? Reporter: Well, that is the big question, David. The white house says the president doesn't want a quick fix. And there is zero indication right now that any of these measures being debated on capitol hill have the votes to pass. We've heard the president say, the ball is in congress's court, but as we have been reporting, this is the reality. This is his measure. He can end this would congress. Cecilia Vega, thank you.

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