Fereydoun Abbasi also rebuked the United States in comments to the IAEA's 55-nation general conference, reflecting Iran's determination to continue defying international pressure aimed at curbing its nuclear program and nudging it toward cooperation with the IAEA inspection.
As such, the speech was bound to give a greater voice to hardline Israel leaders who say that both diplomatic efforts and economic penalties have failed to move Iran, leaving military strikes as the only alternative to stopping it from developing nuclear weapons.
Israeli Prime Minister Benjamin Netanyahu made a direct appeal to American voters on Sunday to elect a president willing to draw a "red line" with Iran.
In the past week, Netanyahu has called on President Barack Obama and other world leaders to state clearly at what point Iran would face a military attack. But Obama and his top aides, who repeatedly say all options remain on the table, have pointed to shared U.S.-Israeli intelligence that suggests Iran hasn't decided yet whether to build a bomb despite pursing the technology and that there would be time for action beyond toughened sanctions already in place.
Tehran denies seeking nuclear arms and Abbasi, an Iranian vice president whom the agency suspects may have been involved in nuclear weapons research, again insisted on Monday that his country's nuclear program is aimed only at making reactor fuel and medical research.
"The Islamic Republic of Iran ... has always opposed and will always denounce the manufacture and use of weapons of mass destruction," he said.
Tehran has long dismissed suspicions that it may re-engineer its uranium enrichment program from making reactor fuel to producing nuclear warheads and says accusations that it has worked secretly on nuclear arms are based on fabricated U.S. and Israeli intelligence. It also frequently accuses the IAEA of anti-Iran bias in its push to ensure that all of Tehran's nuclear activities are peaceful.
But Abbasi's comments Monday were the harshest to date on the agency itself.
"Terrorists and saboteurs might have intruded the agency and might be making decisions covertly," he said. Citing what he said was an example of sabotage last month at an underground enrichment plant, he said IAEA inspectors arrived shortly after power lines were blown up to inspect the premises.
"Does this visit have any connection to that detonation?," he asked.
Alluding to the United States in arguing that pressure on Iran was an attack on all developing nations' nuclear rights, Abbasi invoked U.S-led sanctions on its oil exports and transports and financial transactions as "the ugly face of colonialization and modern slavery."