The US has said it will press for a new set of sanctions to be imposed on Iran over its continued failure to suspend its uranium enrichment programme.
Mr ElBaradei has faced criticism from Europe and the US
It followed a UN nuclear watchdog warning that Tehran was stepping up enrichment and obstructing inspections.
Mohamed ElBaradei is due to address a joint US-Russian conference on nuclear proliferation later on Thursday.
He is set to call on the international community to prevent Iran enriching uranium on an industrial scale.
Mr ElBaradei is expected to voice what many analysts fear - that the focus on halting Iran's enrichment experiments has been overtaken by events, says our correspondent in Luxembourg, Jonathan Marcus.
Mr ElBaradei has suggested that Iran be allowed to keep part of its enrichment programme.
This point of view is at odds with that of the US and of a number of key European governments.
The US and other European allies were so angered by Mr ElBardei's "unhelpful comments" that they were expected to deliver a formal complaint.
Our correspondent says Washington may have some difficulty in persuading all members of the UN Security Council to impose further sanctions.
The US described the International Atomic Energy Agency (IAEA)'s report as "a laundry list of Iran's continued defiance of the international community".
Iran has denied hindering the IAEA and said it will "continue to co-operate".
In March, the UN Security Council imposed a second round of sanctions on Iran for failing to suspend uranium enrichment, prompting Tehran to limit its co-operation with the agency.
However, IAEA inspectors still regularly visit Iran's atomic facilities under the nuclear Non-Proliferation Treaty.
After the IAEA issued its report on Wednesday, the US representative to the UN, Zalmay Khalilzad, said his government was now considering taking further steps against Tehran.
"What we have done so far is not enough. More needs to be done," he said.
The IAEA said its ability to monitor Iran's activities had "deteriorated"
"The time has come to look at additional pressure [...] to bring about a change in Iranian calculations."
The British envoy to the UN, Sir Emyr Jones Parry, said he had not found the IAEA report surprising.
"It's now for the international community to consider how we respond to that," he told reporters.
Sir Emyr said Europe and the other UN Security Council members still expected Iran to meet the obligations it has been set.
"We want a new, improved, better relationship with Iran, but that requires Iran to meet the conditions established by the Security Council and if she does that, then we're in business of having discussions," he added.