Democratic presidential nominee Joe Biden pledged that if he is elected president he will will create a task force to reunite 545 migrant children who were separated from their parents at the U.S. southern border. 

BIDEN HAS MULTIPLE 'PATHWAYS TO GET TO 270' WHILE TRUMP DOES NOT, EX-OBAMA DEPUTY CAMPAIGN MANAGER SAYS

"On his first day as president, Joe Biden will issue an executive order creating a task force to reunite these children with their parents," Biden's campaign said in a newly released ad on Wednesday. 

The American Civil Liberties Union sued the Trump administration over its policy that separated migrant children in 2017 and 2018 from their parents who were being held in government custody for illegal border crossings, part of a "zero-tolerance policy," to crack down on illegal immigration. 

In 2018, U.S. District Judge Dana Sabraw in San Diego, Calif., ordered the families be reunited, but experts from the ACLU say that hundreds of parents who were separated in 2017 still cannot be found.

DEMS MAKE EARLY-VOTING HISTORY AGAINST ARIZONA REPUBLICANS

A court-appointed steering committee could not make contact with 545 children's parents, out of at least 1,030 children whom the committee had telephone numbers for.

At least two-thirds of the parents have likely been deported to their country of origin, the ACLU said. 

The ACLU blasted Trump last week, saying the administration has done little to help attorneys locate parents and reunite children. 

“We are extremely pleased that Vice President Biden has expressed an interest in helping the families who were torn apart by the Trump administration," ACLU attorney Lee Gelernt, the lead lawyer in the family separation lawsuit, said in a statement to Fox News on Thursday. 

"We not only want to see the families reunited in the United States, but provided legal status given what they have been through. The families should also be provided with medical help to deal with the horrific trauma they have suffered.”

WHITE HOUSE'S STEPHEN MILLER WARNS OF 'NATIONWIDE CATCH AND RELEASE' IF BIDEN IS ELECTED

Trump and Biden sparred over the family separation policy at the most recent presidential debate last week. 

"What happened? Their kids were ripped from their arms and separated. And now they can not find over 500 sets of those parents and those kids are alone, nowhere to go. It's criminal," Biden said. 

Trump countered that the children are "so well taken care of," and said his administration is "working on it" when asked what efforts towards reunification are being made. 

CLICK HERE FOR THE FOX NEWS APP

A recent Health and Human Services watchdog report revealed that there were 2,654 children initially determined to have been possibly separated from their parents, the majority of whom were from Guatemala or Honduras.