US President Donald Trump greets a policeman with Border Patrol agents,and military after his visit to US Border Patrol McAllen Station in McAllen, Texas, on January 10, 2019. (Photo by Jim WATSON / AFP)
Washington CNN  — 

President Donald Trump is considering a new rule that could dramatically limit the ability of Central American migrants to claim asylum if they enter the United States by land through Mexico, according to a senior administration official and a source close to the White House.

The regulation is the latest attempt by the Trump administration to toughen the US asylum process and has the potential of affecting a large swath of migrants journeying to the US-Mexico border.

Over recent months, migrants predominantly from Central American countries have accounted for the majority of apprehensions at the southern border. They’ve had to travel through Mexico to reach the border and upon arriving in the US, some have turned themselves in to Border Patrol and claimed asylum.

The regulation would prohibit migrants who have resided in a third country from seeking asylum. It would, therefore, bar migrants transiting through Mexico from being able to claim asylum and as a result, drastically limit who’s eligible for asylum. One official said the regulation would be an interim final rule, which could allow the new restrictions to go into effect immediately.

Politico first reported the proposal.

Trump has grown increasingly frustrated by his inability to stop the flood of migrants from being able to claim asylum in the United States. He has complained that Congress refuses to make changes to asylum laws that could limit frivolous asylum claims.

“They won’t give us the legislation. Whether it’s chain migration or whether it’s lottery, they won’t give us any,” Trump told reporters at the White House on Thursday morning. “And the asylum procedures are ridiculous. No place in the world has what we have in terms of ridiculous immigration laws.”

The President also said he would be making a major immigration announcement this week, although sources told CNN that this asylum change was not expected to be what the President will announce and Trump did not elaborate.

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The regulation is certain to face legal challenges. Under US law, migrants are allowed to claim asylum once on US soil. There’s a caveat, however, for those who come through safe third countries, meaning countries that the US has entered into an agreement with. The United Nations’ refugee agency defines “safe country,” in part, as “being countries in which refugees can enjoy asylum without any danger.”

But Trump’s own statements on Mexico could undercut that definition. In tweets, the President has called Mexico “one of the most dangerous country’s in the world” and claimed that the murder rate in the country is up.

Still, the administration has continued to implement a separate policy that requires some asylum seekers to wait in Mexico for the duration of their immigration proceedings. As of May 21, the US had returned around 6,000 asylum seekers to Mexico, according to the Department of Homeland Security.

The policy, which was rolled out in January, was challenged in court, but the 9th US Circuit Court of Appeals allowed the administration to continue returning asylum seekers to Mexico for the time being.

The panel, while split on some issues, listed a number of factors that went into the decision, including risk of injury in Mexico and negotiations between the US and Mexico.

The 9th Circuit has blocked other administration attempts to restrict asylum, though.

Late last year, the administration tried to bar migrants who illegally cross into the US through the southern border from seeking asylum outside of official ports of entry. A federal judge in California quickly blocked the order, and the 9th Circuit agreed. The Supreme Court eventually upheld a federal judge’s order blocking the new asylum restrictions last December.

The latest attempt to change the asylum process comes amid an increase in illegal border crossings.

In April alone, the Border Patrol arrested 98,977 migrants for illegal entry, many of whom were families – an increase from March. And that trend is likely to continue.

On Wednesday, more than 1,000 migrants were apprehended by US Border Patrol agents – what a DHS official says was the largest group of migrants ever apprehended together. According to the official, the group of migrants, which was made up of mostly families, turned themselves in.