(CNN) More than 200 children from separated undocumented immigrant families remain in US custody, officials said in a court filing Monday night.

Most of the 245 children in custody have parents who were removed from the United States -- 175 children, according to the latest government tally.

Of those, only 18 children are currently in the pipeline to reunite with their parents in their countries of origin, according to court documents. Deported parents of 125 kids in custody have said they don't want their children to be returned to the countries of origin. And there are 32 children in government custody for whom the American Civil Liberties Union has not yet provided notice of whether parents want to reunify or decline reunification, officials said.

An additional approximately 70 children who remain in custody include 27 whose parents are in the US but have chosen not to be reunified with their children, as well as 26 whose parents have been deemed unfit to be reunified. That tally also includes 13 children the US government is working to discharge who have parents in the US. The government says three other children can't be reunited with parents who are in the US at this time because there are red flags for safety or a parent is in criminal detention.

The new numbers appeared in the latest federal court filing in the ACLU class action case over family separations. They come as the Trump administration considers a new pilot program that could result in the separations of kids and parents once again

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