TEHRAN (AFP) - Iranian President Mahmoud Ahmadinejad on Thursday proclaimed Iran as the "most powerful nation" on earth as the country's air force showed off its prowess at a time of mounting tension with the West. "Iran is the most powerful and independent nation in the world," Ahmadinejad told a military parade outside Tehran marking the Islamic republic's annual Army Day, reaffirming one of his favoured slogans. Ahmadinejad said all the branches of the armed forces would react forcefully in response to any attack against Iran's soil and boasted that no one would dare to launch a strike on the country. "The army, the Revolutionary Guards and the Basij (militia) will resist with force and coordination and respond strongly to the slightest aggression," he said. "I am proud to announce today that the Iranian nation's power is of an extent that no major power can dare jeopardise the security and interests of the Iranian nation." To mark the occasion, dozens of fighter jets and other aircraft flew over the parade ground in a bid to show the power of the air force, which has struggled for years under the effects of US sanctions. Among them were US-made F4 and F-5 fighter jets whose construction goes back to the 1960s and 1970s when shah Mohammad Reza Pahlavi went on a massive military spending spree. Also shown were several Saegheh fighter jets which Iran says is a entirely home-produced model but Western experts classify as a derivative of the F-5. Among the weapons on display at the military parade was Iran's longer range Shahab-3 missile, whose range includes Israel and even the fringes of Europe. The model shown had a "baby bottle" nose for extra-dynamic efficiency and was labelled "Ghadr-1" although it was clearly a Shahab-3. A lorry carrying other missiles also carried the slogan "Death to Israel" while "Death to America" had been written on another vehicle. Israeli Prime Minister said Iran will never become a nuclear power. "I can say... that, to my knowledge, and on the basis of what I know and read, I believe the efforts of the international community will succeed, and that Iran will not become a nuclear power," he told the Maariv daily. "There is an enormous effort on the part of the international community to prevent Iran from becoming a nuclear country. Israel plays an important part in those efforts, without leading them." Building on that, and in an allusion to recent threats made against Iran by an Israel minister, Olmert added: "That is why Israel should not resort to threats as made recently." Ahmadinejad repeated his belief that the power of Iran meant the prevailing world order was set to be turned on its head. "Thanks to the resistance of the Iranian people, the great powers have become bogged down. The region and the world must prepare for great changes and the disappearance of satanic powers." The head of the UN atomic watchdog Mohamed ElBaradei said progress by Iran in building more centrifuges to enrich uranium in defiance of international demands is "not very fast". "The rate of progress so far has not been very fast" at Iran's Natanz plant, ElBaradei said after talks with German Foreign Minister Frank-Walter Steinmeier in Berlin. "I think they had in the past 3,000 centrifuges and I think now they have like 3,300 or 3,400. They are not moving very much." "I continue to call on Iran not to speed up the process because we need first to have an agreement with the international community about building confidence before Iran moves with its enrichment programme," ElBaradei said. He was speaking on the sidelines of a two-day international conference on nuclear power in Berlin which began on Thursday.