Arguing that the asylum process into the U.S. is overwhelmed with "meritless asylum claims," the administration moved forward to block asylum seekers who cross the border illegally from then seeking asylum. The move comes as thousands of Honduran migrants caravan through Mexico on their way to the U.S. border.

"His claim is that this is meant to protect the United States against threats from abroad," said Vickie Gass, senior policy advisor for Oxfam’s Central America projects. "These are women, children, elderly young people who are just looking for a chance at life which their own governments aren’t giving them."

Homeland Security Sec. Kirstjen Nielsen said in a prepared statement "Our asylum system is overwhelmed with too many meritless asylum claims from aliens who place a tremendous burden on our resources, preventing us from being able to expeditiously grant asylum to those who truly deserve it."

Lawsuits over the mandate are expected. Critics argue the order violates federal and international laws.