The director of the New York office of the UN high commissioner for human rights has left his post, protesting that the UN is “failing” in its duty to prevent what he categorizes as genocide of Palestinian civilians in Gaza under Israeli bombardment and citing the US, UK and much of Europe as “wholly complicit in the horrific assault”.

“The current wholesale slaughter of the Palestinian people, rooted in an ethno-nationalist colonial settler ideology, in continuation of decades of their systematic persecution and purging, based entirely upon their status as Arabs … leaves no room for doubt.”

Mokhiber added: “This is text book case of genocide” and said the US, UK and much of Europe were not only “refusing to meet their treaty obligations” under the Geneva Conventions but were also arming Israel’s assault and providing political and diplomatic cover for it.

“We must support the establishment of a single, democratic secular state in all of historic Palestine, with equal rights for Christians, Muslims, and Jews,” he wrote, adding: “and, therefore, the dismantling of the deeply racist, settler-colonial project and an end to apartheid across the land.”

Louis Charbonneau, the UN director at Human Rights Watch, told the Guardian that he had made a powerful argument against double standards in the stance of the world body.

By contrast, Anne Bayefsky, who directs Touro College’s Institute on Human Rights and the Holocaust in New York, accused Mokhiber on social media of “overt antisemitism”.

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