The Trump administration has come under harsh criticism from those on all sides of the US political spectrum for its move to scrap a programme that protects from deportation hundreds of thousands of people who were brought into the country without documents as children.
Attorney General Jeff Sessions announced the end to the Deferred Action for Childhood Arrivals (DACA) scheme on Tuesday, angering many but also drawing some support from staunch Trump allies.
DACA has helped nearly 800,000 young people, referred to as Dreamers, get legal status, work permits and driving licences.
The programme's fate now rests with Congress members who will have six months to come to a political solution before DACA officially ends.
Late on Tuesday, Trump tweeted that he would "revisit this issue" if Congress fails "legalise DACA" in six months.
While the move was expected for weeks, Tuesday's announcement drew strong condemnation from many throughout the US.
Barack Obama, the former US president who created DACA in 2012, called the action "cruel" and a "political decision".
"Ultimately, this is about basic decency," he said in a statement on Facebook.
"This is about whether we are a people who kick hopeful young strivers out of America, or whether we treat them the way we'd want our own kids to be treated. It's about who we are as a people - and who we want to be."