The UN High Commissioner for Human Rights Zeid bin Ra'ad Al Hussein on Wednesday slammed US President Donald Trump’s executive order banning travel from certain Muslim-majority countries.
Trump's immigration policies could lead to mass detentions, including children, and collective expulsions would breach international law, said Zeid.
In an annual speech to the UN Human Rights Council in Geneva, Zeid said greater leadership was needed to address a surge in discrimination and "vilification of entire groups such as Mexicans and Muslims" in the United States.
He was particularly concerned about the impact on children "who face being detained, or may see their families torn apart."
Trump on Monday signed a new executive order, which included a travel ban by citizens of six Muslim-majority countries to the US.
The order was a revised version of a travel ban signed in January.
The new order temporarily freezes new visas for Syrians, Iranians, Libyans, Somalis, Yemenis and Sudanese citizens; Iraq was removed from the list of banned countries.
Zeid also criticised the US president's attempts to "intimidate or undermine journalists and judges."
Trump has regularly attacked the media. He issued a statement on February 17 in which he accused several traditionally respected US news organisations — New York Times, NBC News, ABC, CBS and CNN — of providing "fake news," and called them "the enemy of the American people."