Washington designated Palestine Action as a terrorist group, saying the step was part of President Donald Trump's effort to crack down on left-wing groups in its counter-terrorism efforts. Israel's foreign ministry welcomed the designation.
The designation "appears to be both a disproportionate and unnecessary restriction on the rights to freedom of expression, peaceful assembly and association as well as the right to participate in public affairs," the office of United Nations human rights chief Volker Turk said.
"Expansive use of the term 'terrorism' has been documented to have a chilling effect on civic space."
Britain previously banned Palestine Action as a terrorist organisation, which was also condemned by Turk's office. The UK's Supreme Court has said it will hear an appeal against a lower court ruling that Britain's decision to ban the campaign group as a terrorist organisation was lawful.
Palestine Action has targeted Israel-linked defence companies in Britain, especially Israel's largest defence firm Elbit Systems, often blocking entrances or spraying red paint.
It was banned by Britain shortly after a break-in at the Royal Air Force's Brize Norton base in June 2025 in which activists damaged two military planes. The UK ban on the group had prompted protests in which about 3000 people were arrested.
The group says its activities "have always been about saving lives by disrupting the Israeli war machine" and opposing Israel's assault on Gaza.
It says it uses "disruptive tactics" to target "corporate enablers of the Israeli military-industrial complex."
The Trump administration has attempted to deport pro-Palestinian foreign protesters, threatened a funding freeze for universities over protests, enforced social media screening for immigrants and sanctioned critics of US ally Israel.
Ben Saul, UN special rapporteur on human rights and counter-terrorism, and Francesca Albanese, a UN expert on the occupied Palestinian territories, also raised concerns about Washington's designation.
Such steps aim to silence critics, said Albanese, who herself has been sanctioned by the US after she called Israel's military actions in Gaza a "genocidal campaign" and called for war crime prosecutions.
Sarah McLaughlin, senior scholar of global expression at free speech group FIRE, said "we must reject that censorship - not import it."
