The U.N. human rights chief is urging the Trump administration to end new policies separating migrant children from their parents after entering the United States from Mexico.

Zeid Ra’ad al-Hussein cited an observation by the president of the American Association of Pediatrics that locking the children up separately from their parents constituted “government-sanctioned child abuse,” The New York Times reported.

“The thought that any state would seek to deter parents by inflicting such abuse on children is unconscionable,” al-Hussein, a Jordanian prince, said.

He spoke at Monday’s opening of a regular Human Rights Council session, his last before his term ends in August.

The greater U.N. also expressed similar sentiments.

Stéphane Dujarric, spokesperson for Secretary-General António Guterres, said in a statement: “As a matter of principle, the Secretary-General believes that refugees and migrants should always be treated with respect and dignity, and in accordance with existing international law. Children must not be traumatized by being separated from their parents. Family unity must be preserved.”

Amid the international outcry, Homeland Security Secretary Kirstjen Nielsen said Monday that the growing crisis at the U.S.-Mexico border “is not new.”

“We will not apologize for the job we do or for the job law enforcement does for doing the job that the American people expect us to do,” Nielsen told the National Sheriffs’ Association during a speech in New Orleans. “Illegal actions have and must have consequences. No more free passes, no more get out of jail free cards.”

The separation of immigrant children from their parents at the border has drawn a good deal of criticism, targeting the policy instituted last month by Attorney General Jeff Sessions. That policy says that any adult who enters the U.S. illegally is to be prosecuted criminally.

U.S. protocol does not allow children to be detained with their parents because they, unlike their moms and dads, aren’t charged with a crime.

Fox News' Ben Evansky, Sam Chamberlain and The Associated Press contributed to this report.