Mohammed ElBaradei, the head of the International Atomic Energy Agency, also warned a 145-nation conference that his organization is increasingly stretched in trying to monitor responsibilities that include nonproliferation in countries like Iran and preventing terrorists from acquiring the bomb.
"All is not well with the IAEA," ElBaradei said, asking the opening session of the agency's general conference for more money and authority.
The meeting has traditionally been an annual chance for the United Nations nuclear monitoring agency's member countries to plan general nuclear policies that range from strengthening nonproliferation to programs of medical and scientific benefit.
Decisions have been traditionally made by consensus, a practice that had led all sides to bridge sometimes substantial differences and compromise on most issues for most of the general conference's 52-year history. A vote on any topic is unusual and considered a huge dent in the meeting's credibility.
But Arab countries, backed by Iran and frustrated over Israel's refusal to put its nuclear program under international purview, are pushing to force a vote for the third year running.
After losing the vote two consecutive years, Islamic nations are threatening to up the ante this year, warning they will call for a ballot on every item, no matter how uncontroversial.
As in the past two years, Islamic IAEA members are expected to put forward a resolution urging all Mideast nations to refrain from testing or developing nuclear arms and urging nuclear weapons states "to refrain from any action" hindering a Mideast nuclear-free zone.
Israel, widely considered the only Mideast nuclear weapons state, objects to being singled out as it was in a separate Arab-backed resolution that was defeated last year and is pursuing a vote on the more general nuclear-free zone measure.
Focusing on Israel by name "is substantially unwarranted and flawed," said a letter prepared for review by the conference from Israel Michaeli, the Jewish State's IAEA representative.
Sponsors of the item should instead "address the most pressing proliferation concerns in the Middle East," the letter said, alluding to Iran's refusal to stop uranium enrichment in defiance of U.N. Security Council sanctions and allegations that Iran once planned to make nuclear weapons.
On Saturday, the U.N. Security Council approved a resolution critical of Iran and in his comments Monday, ElBaradei urged the country to "implement all transparency measures ... required to build confidence in the exclusively peaceful nature of its nuclear program."
"This will be good for Iran, good for the Middle East region and good for the world," he said.
Iran, along with ally Syria, figures directly at the Vienna conference because they are among four nations seeking their region's nomination for a seat on the IAEA's decision-making 35-nation board.
Iran is running to counteract a U.S. push to have Afghanistan or outsider Kazakhstan elected over Syria, which is under IAEA investigation for allegedly hiding a secret nuclear program, including a nearly completed plutonium producing reactor destroyed last year by Israel.
Afghanistan has so far refused to bend to pressure to withdraw from the race, diplomats told the AP. Without agreement, it will come to another - almost certainly divisive - vote.