The Trump administration is reportedly set to announce a rule change which would allow the government to hold migrant families in detention camps indefinitely.

Currently, children crossing illegally into the US from Mexico can generally be held for a maximum of 20 days, a limit Donald Trump has blamed for encouraging undocumented families to arrive at the border.

Under the new rule, which would likely require court approval, the Department for Homeland Security (DHS) could hold children in detention for the entirety of their immigration proceedings, which can take months or even years.

The move could be made public on Wednesday, according to ABC News, which spoke to government officials on condition of anonymity.

The plan appears similar to a DHS proposal last year that would have scrapped some of the restrictions in a 1997 court settlement known as the Flores Settlement Agreement, which established among other things how long detained children can be held.

The proposal, which was not enacted at the time due to a surge of migrants arriving at the border, argued the government could terminate some of the restrictions, including the 20-day limit, if it could establish its own regulations.

NBC News reported Trump administration officials expect to be sued in court imminently by opponents to the plan.

The possible holding of children indefinitely comes following an announcement by Customs and Border Protection (CBP) that it will not vaccinate migrant families in detention ahead of this year’s flu season.

“In general, due to the short-term nature of CBP holding and the complexities of operating vaccination programmes, neither CBP nor its medical contractors administer vaccinations to those in our custody,” a CBP spokesperson told CNBC.

Having gone years under Barack Obama without any deaths of children while in US immigration custody, at least three juveniles have died in detention facilities in the past year alone under the Trump administration, doctors have said.

Earlier this year, Trump administration lawyers unsuccessfully argued in court it should be able to force detained migrant children to sleep on concrete floors and deprive them of soap and toothbrushes, in what amounted to another challenge to the 1997 Jenny Lisette Flores v Edwin Meese settlement.