Transcript for Trump faces pushback after declaring national emergency to fund border wall

Now to the pushback over president trump declaring a national emergency to fund a border wall. The acting secretary of defense saying he has not yet determine if the border wall is a military necessity or how much money the Pentagon would authorize to be used for it. ABC's white house correspondent Tara Palmeri is in west palm beach where the president is spending the weekend. Tara, good morning. Reporter: Good morning, whit. That's right. The president is facing political and legal backlash over his decision to declare an emergency so he can tap into about $6 billion in treasury and military funds to build the wall himself. Now overnight, acting defense secretary Patrick Shanahan telling reporters he has to determine if a wall along the Mexican border is necessary. He also hasn't decided how much money he can realistically put towards the wall. He added he still hasn't spoken to the president since the declaration was made on Friday. Since president trump made that decision, the aclu, public citizen and the state of California filed lawsuits against the administration for an overreach of executive power. Ten Republican lawmakers have voiced their disapproval and house Democrats now are drumming up support for a resolution that would formally terminate the emergency declaration. They only need four Republicans in the senate to pass that bill and get it on the president's desk which could lead to the first veto of his administration. Dan. Tara, thank you. Let's bring in ABC's Raddatz who is in Washington where she'll be co-hosting "This week" later this morning. Martha, good morning to you. So you have covered the U.S. Military for many, many years. Can the defense secretary acting or not, really block the president from re-allocating military funds to build this wall and what would that do to Shanahan's job security? Reporter: Patrick Sha as Tara said, he's the acting defense secretary of course. Jim Mattis quit as defense secretary before that, so Shanahan is acting. He said he has been looking at these regulations for several weeks in anticipation that the president would declare an emergency and as Tara said, he says he does have the discretion to utilize military construction funds to support military operations and he had not yet determined whether it's a military necessity, but I suspect, Dan, he will determine that very quickly. Of course, we do have members of the U.S. Military, active duty and guard, down there on the border so I suspect he will approve this. I think he wants to do it the right way. I think he wants to go through all the regulations and he wants to talk to homeland security and then will likely make that determination. Because if you talked about job security, Dan, that would not be good for his job security. I can only imagine. You have the Republican congressman Jim Jordan on your show this morning. He's one of the co-founders of the freedom caucus, which is a right wing group of legislators. How do Republicans feet this emergency declaration given that many of them criticized then-president Obama repeatedly for executive overreach? Reporter: Well, Jim Jordan, I'm certain you will hear him say that he supports the president in this. He has said it before. He just says it is an invasion just like the president. He basically echoes president trump's words, but you have got others like Marco Rubio saying there is no crisis that justifies violating the constitution. Senator Susan Collins said it undermines the role of congress and the appropriations process. There is certain to be some sort of fight on capitol hill, but I think you will hear Jim Jordan support the president and we'll try to push him on that and why. Some divisions among the Republicans on this one. Martha Raddatz, always a pleasure to talk to you on a Sunday morning, and I want to remind everybody. Martha will have much more on the president's national emergency declaration later this morning on "This week." She'll speak to the attorney general Javier basera, and Tammy Duckworth and Jim Jordan. They will all be weighing in and the powerhouse round table and that's coming up on "This week" on ABC.

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