"International tribunals are needed to address the universal magnitude of ISIL crimes against humanity," said Murad, using another acronym for the group.

"We asked you to refer this genocide to the ICC or establish a court by treaty. It is time for the international community to do more. It is time to act," added the 2018 Nobel winner, herself a victim of Islamic State violence.

Murad referred to the latest report from a group of UN investigators, headed by Karim Asad Ahmad Khan and created in 2017 to probe crimes committed by IS.

"The evidence collected by Mr Khan and the unit team affirmed the conclusion reached by the United Nations in 2016. ISIL crimes against Yazidis constitutes genocide," said Murad.

"The Council must now prioritize and accelerate concrete action to address the findings," she added.

The report released Monday completed probes into attacks against the Yazidi community in the Sinjar region and the mass killing of unarmed cadets and military personnel at Tikrit Air Academy in June 2014.

Khan told a press conference presenting the findings there was "clear and convincing evidence that genocide was committed by ISIL against the Yazidi as a religious group."

"Evidence collected by the Team had also confirmed ISIL was responsible for acts of extermination, murder, rape, torture, enslavement, persecution and other war crimes and crimes against humanity perpetrated against the Yazidis," he said.

The report found the "repeated deployment of chemical weapons by ISIL against civilian populations in Iraq between 2014 and 2016, as well as the testing of biological agents on prisoners."

Khan is due to take up his new role as the ICC's chief prosecutor in June. In the past he has called for trials along the lines of that of Nazi leaders at Nuremberg.

IS, defeated in Iraq at the end of 2017, left behind more than 200 mass graves that could contain up to 12,000 bodies, according to the UN.