Trump said the order "will solve that problem" of children being separated from their parents, but that it wouldn't end his administration's "zero tolerance" policy of charging everyone who attempts to cross the U.S. -Mexico border illegally, a decision that led to the current crisis.
In Washington, activists stood next to a table occupied by Department of Homeland Security Secretary Kirstjien Nielsen in a Mexican restaurant, voicing criticism of the administration's policy, according to video obtained by Reuters.
Trump was a meeting with members of Congress Wednesday when he addressed the increase in the number of migrant children being separated from their families at the border.
The plan, as described by administration officials, would keep families together in federal custody while awaiting prosecution for illegal border crossings, potentially violating a 1997 court settlement limiting the duration of child detentions.
The order aims to end the separation of most migrant families by detaining them together while they await their court dates in criminal and immigration court. Orrin Hatch, R-Utah, - usually a reliable Trump ally - also likely played a role.
"We have to be very strong on the border, but at the same time we want to be very compassionate", Trump said at the White House during a meeting with lawmakers that was opened to the media.
Nielsen traveled to Capitol Hill Wednesday afternoon to brief lawmakers.
"To find a way to welcome the refugee and the immigrant -- to be big enough and wise enough to uphold our laws and honor our values at the same time -- is part of what makes us American", said the former president, while acknowledging that Wednesday was World Refugee Day. Blame is also placed on the parents for putting their children in this position by illegally crossing borders with them.More news: PM says £20bn cash boost for NHS 'must be invested in technology'
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"I'll be doing something that's somewhat pre-emptive but ultimately will be matched by legislation I'm sure", Trump told reporters at the White House.
What just happened: President Donald Trump officially reversed his debunked argument that he had no authority to stop separations of undocumented immigrant families at the border.
In a speech to a business group earlier Tuesday, Trump said he wanted to see legislation deal with family separation, which, he said, "We don't want". She was heckled at a restaurant Tuesday evening and has faced protesters at her home.
It's unclear how long it will take for Trump's order to be implemented.
The president made the dramatic u-turn Wednesday afternoon amid a growing outcry over distraught children being separated from their families and put in detention centers.
"I'll be signing something in a little while that's going to do that", Trump said. The official did not know what prompted Trump to change course.
U.S. Customs and Border Protection said on Tuesday that 2,342 children had been separated from their parents at the border between May 5 and June 9. They met with Trump with hopes of finding a solution that holds to his hard-line immigration policy and ends the practice of taking migrant children from parents charged with entering the country illegally.
The president and his top aides have insisted for days that they had no choice but to separate children from their parents due to unspecified United States laws. Other recent rulings, upheld on appeal, affirm the children's rights to a bond hearing and require better conditions at the Border Patrol's short-term holding facilities. Besides appropriating $25 billion for a wall along the southern border, the measure would provide six years of renewable legal status to young immigrants brought to the country by their parents and living here without legal authorization, known as Dreamers.