The US Government is reportedly introducing a new fast-track process to deport migrants without going to court.
The new rules state that migrants who cannot prove they have been in the US continuously for more than two years can be immediately deported.
This is expected to be implemented with immediate effect after it is published sometime later today.
Several rights groups say hundreds of thousands of people could be affected.
But the policy may be challenged in the court by the American Civil Liberties Union.
The US immigration policy has come under increasing scrutiny in recent months.
One issued raised in particular were the conditions at the country’s detention centres on the southern border with Mexico.
US Border Patrol says it has made 688,375 apprehensions on the south-west border since October 2018, more than double that of the previous fiscal year.
Analysts predict US President Donald Trump will make hardline immigration control a key element of his re-election campaign in 2020.