Transcript for Mayors across the country are challenging Trump's sanctuary city proposal
We want to turn to politics now and the increasing tensions between the president and his political foes over developments at the border. Images like these of migrants heading for the U.S. Continuing to frustrate president trump. To frustrate president trump. The president pushing undocumented immigrants catching some of his own team off guard, but some big city leaders are now welcoming the idea. ABC white house correspondent Tara Palmeri with more. Reporter: Tonight, mayors across the country are challenging president trump's latest proposal to transport migrants from detention centers along the southern border to so-called sanctuary cities. From Oakland -- This is an outrageous abuse of power and public resources. Reporter: -- To Seattle. We in Seattle and this region will stand up against the president who divides America. Reporter: To San Jose. The threats of the president certainly don't amount to threats to us. Reporter: The city's leaders including Chicago's incoming mayor saying they will welcome migrants. We're going to do everything we can to make sure that people who come to the city, whatever their immigration status is, are going to be treated fairly and with respect. Reporter: Just 24 hours ago, the white house saying the idea to bust migrants was floated and rejected. It was dismissed by the department of homeland security, but the president contradicted his own administration. We are looking at the possibility, strongly looking at it to be honest are you. Reporter: Tonight a white house spokesperson telling ABC news they are taking the proposal seriously, and they have launched a review on how it would work and how much it would it's the latest sign of the president's growing frustration with what he calls a crisis at the southern border. Last month 103,000 migrants were either apprehended or stopped oath border. A highest number in over a decade. They're coming like it's a picnic, because let's go to disneyland. Reporter: The plan would involve moving them to these locations. There are more than 30, because they choose not to follow immigration laws. They want more people in their sanctuary cities, we'll give them more people. We'll give them a lot. We'll give them an unlimited supply. Let's see if they are so happy. They say, we have open arms. Let's see if they have open arms. And Tara Palmeri joins us from the white house. The president locked in a few battles besides the one on the border including one also with congressional Democrats who want to see his tax returns, and tonight we're learning about a new deadline? Reporter: Tom, chairman of the house Richard Neal has sent a second letter requesting six years of the president's business and personal tax returns. He has also set a new deadline, April 23rd at 5:00 P.M. For the irs to hand over these tax returns. Now secretary of the treasury Steven mnuchin has rebuffed this request calling it arbitrary and says he may not make the deadline. Tom, if he does not make that deadline and they ignore the request, it will likely end up in federal court. Tara Palmeri tonight with that new reporting.
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