Updated

The Department of Health and Human Services backed away late Wednesday from an official's claim that more than 2,000 immigrant children separated from their parents at the U.S.-Mexico border would not be reunited with their families right away despite President Trump's executive order aimed at keeping families together.

Kenneth Wolfe, a spokesman for the Department of Health and Human Services [HHS]' Administration for Children and Families [ACF], initially told reporters the children's cases would proceed through the system as usual.

"There will not be a grandfathering of existing cases," Wolfe said, according to The New York Times.

Hours later, ACF spokesman Brian Marriott told reporters: "An ACF spokesperson misspoke earlier regarding the Executive Order signed today by the President. It is still very early and we are awaiting further guidance on the matter."

Wolfe spoke hours after President Trump signed the order reversing the separation policy after days of public uproar. The order, which preserves the administration's "zero-tolerance" policy toward illegal border crossers, aims to keep families together while they are in custody. However, it also creates a new legal headache for the administration over a 21-year-old class action settlement -- known as the Flores settlement -- mandating that families can be detained only for 20 days.

Justice Department lawyers were planning to file a challenge to the agreement, asking that a judge allow for the detention of families until criminal and removal proceedings are completed.

HHS Secretary Alex Azar told Fox News' "Special Report" that before families can be reunited, "we're going to have to see how the implementation of the executive order goes.

"The Department of Homeland Security's going to have to work with the court and ensure that they are able to keep these families as an integrated unit in detention facilities pending their criminal prosecution of the parents and/or the deportation of the whole family for violation of our immigration laws," Azar said.

The policy put in place by the Trump administration last month moved adults to the custody of the U.S. Marshals Service and sent many children to facilities run by HHS. The children then were turned over to HHS within 72 hours and categorized as unaccompanied minors who eventually would be placed with sponsors.

Azar told Fox News on Wednesday that it takes "about 58 days" for HHS to place the children with sponsors.

Peter Schey, class-appointed counsel in the Flores case, told The Associated Press on Wednesday there was nothing in the agreement preventing Homeland Security officials from detaining children with their parents, "as long as the conditions of detention are humane and the child remains eligible for release, unless the child is a flight risk, or a danger to herself or others, or the child's parent does not wish the child to be released."

He said he was looking into whether the court could block deportations of parents until they have been reunited with their children, and whether it could force the Trump administration to reunite those separated.

"The Department of Homeland Security will do what is possible to hold illegal border crossers accountable while also holding families together as long as the law allows. The only solution is for Congress to authorize detention and prompt removal for illegal families and minors," DHS Press Secretary Tyler Q. Houlton told Fox News.

Fox News' Bret Baier, Eben Brown, Jake Gibson and The Associated Press contributed to this report.