The US Secretary of State says the group "is genocidal by self-proclamation, by ideology and by actions"
US Secretary of State John Kerry has accused Islamic State of committing genocide against religious and minority groups.
Mr Kerry said in a news conference that "in my judgment, Daesh is responsible for genocide against groups in areas under its control including Yazidis, Christians and Shia Muslims".
He added that the militant group "is genocidal by self-proclamation, by ideology and by actions”.
CNN reports that earlier this week the US House of Representatives unanimously passed a resolution labelling the IS atrocities against Christian groups in Syria and Iraq as "genocide".
Genocide is officially defined by the UN as "acts committed with intent to destroy, in whole or in part, a national, ethnic, racial or religious group".
Calls to label IS atrocities as genocide have been growing, with the European Parliament having also unanimously passed a resolution in February recognising the group's killing of religious minorities in the Middle East as genocide.
In a report earlier this year, the UN Assistance Mission for Iraq and the UN's human rights office documented widespread abuses by IS in Iraq that "in some instances amount to war crimes, crimes against humanity, and possibly genocide".
The group is also said to have taken thousands of Yazidi women and girls as slaves.