The probe, headed by former South African Judge Richard Goldstone, concludes that Israel "committed actions amounting to war crimes, possibly crimes against humanity" during its Gaza offensive in December last year.
It asks the UN Security Council to call on Israel to conduct "appropriate investigations," to monitor them, and to refer the matter to the ICC if they're deemed not to meet international standards.
The report found that the firing of rockets by Palestinian armed groups also amounted to war crimes, and called for a similar process of accountability for the Gaza authorities.
But the 34-page summary devoted much less space to the Palestinian violations, and particularly slammed what it called Israel's disproportionate use of force.
UN chief 'reluctant'
Despite the strong conclusions, there is scepticism here about how far these recommendations will go - indeed whether the matter will even get on to the UN Security Council's agenda.
The first step is for the UN's Human Rights Council which commissioned Mr Goldstone's fact-finding mission to request UN Secretary General Ban Ki-moon to bring the matter to the attention of the UN Security Council.
When asked whether he would do so, Mr Moon avoided answering the question directly, instead expressing support for Mr Goldstone's report.
"I have directed our staff to fully review the contents of this, upholding the principles of accountability," he told the BBC.
"I regard that in addressing all these issues, wherever and whenever there are violations of international human rights law, international humanitarian law, these issues should be addressed with a full accountability."
Mr Ban had earlier commissioned his own investigation into Israeli damage of UN institutions in Gaza.
He reported a summary of its conclusions to the UN Security Council, but it was never made public in its entirety and was not taken up by the council for further action.
One long-time UN observer suggested the UN chief may be reluctant to deal with what could turn into a diplomatic firestorm.
"I think he feels that he burned himself with his own Gaza report, and this one is much more comprehensive and even more politically sensitive, so I think he will not be eager to do it," the observer said.
If the issue does get onto the council agenda, it seems unlikely to result in the concrete action requested.
'Dishonest' report
Certainly Israel will do all it can to make sure of that.
"We have to look into it, speak with the secretary general and then have a plan of action. We are not going to let it go," the Israeli ambassador to the UN, Gabriela Shalev, told the BBC.
She noted that Israel had been taken by surprise by the timing and location of the announcement.
Israel has strongly rejected the report as "political, unbalanced and dishonest".
It refused to co-operate in the fact-finding mission, saying the mandate prejudged the outcome.
And it defended its own investigations carried out by the military and government ministries.
These were dismissed by Mr Goldstone as "pusillanimous" because, he said, they relied almost exclusively on testimony from Israeli soldiers and included virtually no evidence from Palestinian victims.
"I don't think we will change [because of the report]," said Ms Shalev.
"I know our Supreme Court and the ethics of the Israeli Defence Forces, and every complaint is being looked into. Hundreds are being looked into. Palestinians can bring petitions to the Supreme Court.
"I hope that our friends will support us. We don't have many, but reliable ones like the United States and the Europeans. And they will know we are looking into incidents and don't need help from the outside," Ms Shalev said.
Accountability plea
The expectation here is that Washington, Israel's most reliable friend, would veto any UN Security Council resolution on the matter, as it has done in the past with UN resolutions to which Israel objects.
Perhaps the most that can be expected is a hearing. "There's always a briefing when you want to let off steam," said the UN observer.
But others say the significance of Mr Goldstone's report was precisely his call for accountability, and a timetable to achieve it.
Indeed, the judge stressed: "I think we should all rejoice in living in a world today where there is accountability for war crimes. There wasn't until very recently - it's a very new situation, and it's very important that there should be… no impunity for international crimes that are committed".
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