Israel would be "utterly insane" to attack Iran, outgoing International Atomic Energy Agency chief Mohamed ElBaradei said in an interview with German daily Der Spiegel Saturday. "That would turn the region into one great fireball, and the Iranians would immediately begin building the bomb - with the support of the entire Islamic world." In the interview, ElBaradei called on Teheran to take advantage of the US's newfound willingness to negotiate over the nuclear issue. "I advise the [officials] I meet from Iran: seize the hand that Obama is offering you," he said. ElBaradei, with whom Israel has had a rocky relationship, is stepping down after a 12-year tenure. While Israel has taken no formal stance regarding who it would like to succeed ElBaradei, government sources in Jerusalem seem to be leaning towards the Japanese candidate, Yukiya Amano. The 35 board-member nations of the International Atomic Energy Agency failed to elect a new agency chief in their first round of voting. The race is important because ElBaradei's successor will influence how the world meets the nuclear challenges posed by extremists like Iran and Syria that are thought to be pursuing the bomb. Non-proliferation is the IAEA's most high-profile task. Herb Keinon, Hilary Krieger and AP contributed to this report.