Iran, accused by the United States and Israel of using its nuclear energy drive as cover for weapons ambitions, has always sought to counter those claims by working within the framework of the International Atomic Energy Agency (IAEA).
But with ElBaradei's last report on Iran notable for its critical tone and the IAEA chief saying the prize will "strengthen his resolve", Iranian officials were unafraid to admit their concern for the future course of events.
"There are two ways in which to view the award of this prize. The optimistic hypothesis is that the prize will reinforce the role of the agency and the technical work it does to prevent the proliferation of nuclear weapons.
"The pessimistic hypothesis is that with this prize, Mr ElBaradei will become closer to the political position of the United States and the Europeans, especially on the nuclear issue. And he will put more pressure on Iran.
"In my opinion I think that the second hypothesis is the closer to reality," Jalali concluded.
Israeli Deputy Prime Minister Shimon Peres, himself a Peace Prize winner, has already described the award to ElBaradei and his watchdog as a warning to Iran.
"It is a warning to Iran because Iran is today the biggest and most dangerous problem," he told Israeli public radio.
ElBaradei was quick to pledge that the award would "strengthen my resolve and those of my colleagues to speak the truth to power", without being more specific.
The prize comes at a critical moment in the long running standoff over Iran's nuclear programme after IAEA in September passed a resolution finding the country in breach of the nuclear Non-Proliferation Treaty (NPT).
Negotiations between Iran and Britain, France and Germany to find a diplomatic solution to the crisis broke down in August, when Iran resumed nuclear fuel cycle work in defiance of a pledge to freeze such activities during the talks.
The resolution paved the way for Iran to be hauled before the UN Security Council for possible sanctions over its nuclear programme, an outcome that the talks with the EU-3 had attempted to avoid.