But others, including the president's daughter, argued for a speedy end to the separations.
Signing an executive order to reverse his own administration's practice would also be unnecessary since nearly everyone in Washington, apart from the President, agrees that he already has the power to end the separations any time he wants.
It comes amid widespread condemnation of President Trump's zero-tolerance policy on migrants at the USA southern border after emotive footage showed deeply distressed children crying for their families.
Video footage of children sitting in cages and an audiotape of wailing children had sparked anger as the images were broadcast worldwide.
"We need to embrace our legacy as a safe haven for the persecuted and stop subjecting bona-fide refugees to further trauma by locking them up while they pursue their lawful claims to relief", Tonello said. "We have record-setting numbers in every way economically, but we want to solve this immigration problem, which is going on for four years more". "This is a policy, and understand this - this was a policy invented, implemented and executed by President Donald Trump".
I appreciate the need to enforce and protect our worldwide boundaries, but this zero-tolerance policy is cruel.
"Ivanka feels very strongly".
Earlier, a defiant Trump sounded unfazed by the mounting pressure to alleviate the situation before it ruptures into a public relations disaster for his party. And it was the fault of Congress rather than Trump.
He had tried to blame Democrats for the policy of separating children from parents and force them into concessions, including funding for a wall he wants to build along the border with Mexico. "We have zero tolerance for people that enter our country illegally", Trump told reporters in the Oval Office of the White House as he signed the executive order.
Trump's family apparently played a role in his turnaround. It also calls into question numerous administration's recent claims about the basis of the "zero tolerance" policy that was announced by Attorney General Jeff Sessions in April.
Trump's executive order states the administration will "maintain family unity, including by detaining alien families together where appropriate and consistent with law and available resources". Any attempt by the government to modify the agreement would likely face opposition from the lawyers who negotiated it, according to representatives of immigrant rights organizations.
The president and his top aides have insisted for days that they had no choice but to separate children from their parents due to unspecified United States laws.
A spokesman for the Administration for Children and Families told The New York Times that the children are not expected to be reunited with their parents.
"We're signing an executive order". Children don't belong in jail at all, even with their parents, under any set of circumstances. "Instead of protecting traumatised children, the President has directed his Attorney General to pave the way for the long-term incarceration of families in prison-like conditions", said Democratic Leader Nancy Pelosi.
"The Trump Administration must reverse its policy of prosecuting vulnerable people fleeing three of the most unsafe countries on earth, who are attempting to seek safe haven in America".
It also directs Defense Secretary Jim Mattis to find housing for these families and to build facilities if necessary. First Lady Melania Trump encouraged Trump to act on his own if Congress wasn't able to, a White House official said. Hatch and 12 other GOP senators - including John McCain, R-Arizona, and Lamar Alexander, R-Tennessee, - co-signed a letter on Tuesday to the Justice Department asking that the administration pause the separation of families until Congress addresses the issue. But Republicans said they were uncertain if either measure would have enough support to be approved.
"I am appalled by the reports and images from detention facilities in Texas and other states along the border, where more than 2,300 children have been separated from their parents by border patrol agents", Lee wrote in a letter to the United Nations.