"The decision to make migrants wait in Mexico while processing asylum claims only continues this Administration's cruel policies to stem legal immigration to our nation," Castro said in the release on Thursday.
Earlier in the day, Homeland Security Secretary Kirstjen Nielsen said in a press release that asylum seeking migrants who cross the US southwest border will be sent back to Mexico where they must wait for a ruling by immigration courts on their asylum applications.
US laws, generally, allow anyone who makes it into the United States, legally or illegally, to apply for asylum.
However, the new US policy attempts to address a 20-fold increase over the past five years in illegal aliens who claim a credible fear of persecution — the first step to asylum. Until now, the claim gave migrants an opportunity to remain in the country during legal proceedings whether or not they have a valid asylum claim, according to Nielsen’s release.
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Meanwhile, Mexican Foreign Ministry said Thursday in a statement that Mexico is ready to temporarily host on its territory refugees from other countries, sent back from the United States.
"For humanitarian reasons, it [Mexico] will authorize the temporary entrance of certain foreign individuals coming from the United States who entered that country at a port of entry or who were detained between ports of entry, have been interviewed by U.S. immigration authorities, and have received a notice to appear before an immigration judge," the statement read.
American Civil Liberties Union (ACLU) Border Rights Center advocacy manager Cynthia Pompa argued in a press release on thursday that Mexico should not enable the Trump administration's policy forcing asylum-seekers to remain in the country.
"Mexico should not enable the Trump administration's anti-immigrant agenda," Pompa said.
Pompa called on both the US and Mexican governments to change their approach on immigration, adding that the United States must prioritize port of entry reforms and allocated resources to promptly and fairly process asylum-seekers on the US side of the border.
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"Forcing these families, many with small children, to be trapped in Mexico while their claims await adjudication in the US also offends due process and endangers lives," Rickerd said.
As described, the Trump administration policy would condemn migrants to fend for themselves and would expose them to some of the same sorts of violence that they experienced in Central America, Rickerd added.