Speaking at the UN in New York, the British-Lebanese human rights lawyer, who represents victims including Yazidi rape survivor Nadia Murad, stated IS had declared it will "destroy" the country's Yazidi ethnic group through murder, rape and forced conversions, and is also attacking Christians, and Shia and Sunni Muslims.

The wife of actor George Clooney, who is based at Doughty Street Chambers in London, accused the UN of "inaction" in a powerful speech, in the presence of UN members including Iraqi Prime Minister Haider al-Abadi.

"The UN was created as the world's way of saying 'never again' to the genocide perpetrated by the Nazis," she told UN members, reported the BBC. "And yet here we are, 70 years later, discussing the UN's inaction in the face of a genocide that we all know about, and that is ongoing."

The U.K. is drafting a Security Council resolution to establish a UN investigation, and Amal urged Iraq's Prime Minister to formally send a letter to the UN Security Council requesting the inquiry so the 15-member council can vote to set up an investigation into crimes by the group in Iraq.

The 39-year-old also called for mass graves to be preserved and exhumed, and witness evidence to be recorded, even if it was not supported by the Iraqi Prime Minister.

Amal, who is pregnant with twins, looked chic in a butter yellow Bottega Veneta dress and coordinating coat as she condemned the "passive" response by the world's nations to the campaign to investigate its crimes and bring the perpetrators to justice.

"Don't let this be another Rwanda, where you regret doing too little, too late. Don't let Isis (Islamic State) get away with genocide," she ended her speech.