TEHRAN (AFP) - Iranian President Mahmoud Ahmadinejad on Monday ruled out any talks with world powers on Tehrans nuclear drive, but said he was open to a debate with US President Barack Obama. We have said this before and we are saying it right now, that we will not talk about the nuclear issue with those outside the IAEA, he told journalists. The Iranian nation will not allow anyone outside the IAEA to discuss our nuclear issue, said Ahmadinejad, who is running for a second term in office in the June 12 presidential election. The N-issue is over for us. The talks outside the IAEA will only be about participation in the management and bringing peace to the world, he said. However, he said he was ready to have a debate at the United Nations with Obama to study the root of world problems, adding that he welcomed the change in policy from the new US leader who has said he was open to dialogue with Iran. EU foreign policy chief Javier Solana held talks with Iranian nuclear negotiator Said Jalili in April about discussions with the group of world powers known as the P5-plus-1 on Tehrans controversial atomic activities. Solana has been authorised by the six powers-UN Security Council veto-wielding permanent members Britain, China, France, Russia and the United States plus Germany-to discuss the issue with Tehran. In April, Iran said it was ready for constructive dialogue with the world powers, while at the same time vowing to continue with its nuclear activities which have been the subject of an IAEA investigation for several years. The West fears that Irans nuclear drive could be a cover for efforts to build an atomic bomb, but Tehran insists it is aimed purely at generating electricity for a growing population. Ahmadinejad has said previously that Tehran would present its own package of proposals to the six powers-a new version of proposals offered by Iran in May 2008, which proposed the formation of consortiums to enrich uranium and manufacture nuclear fuel, including one in Iran. Ahmadinejads remarks come after US chairman of the Joint Chiefs of Staff Admiral Mike Mullen said in an interview on Sunday that Iran was moving closer to acquiring a nuclear weapons capability. Certainly from what Ive seen in recent years, Iran is on a path to develop nuclear weapons, he told ABC television. Most of us believe that it is one to three years (away from acquiring nuclear weapons), depending on assumptions about where they are right now. But they are moving closer clearly and they continue to do that, he said. And if you believe that is their strategic intent, as I do and certainly as my Israeli counterpart does, thats the principal concern. Israels military intelligence chief asserted in March that Iran will have the capacity to build a nuclear bomb within a year, but was not rushing to produce one. However, Mullen said a military strike against Iran right now would be incredibly serious, as well as the unintended consequences of their achieving a weapon. Thats why this engagement, dialogue is so important, he said. Ahmadinejad said on Monday that he welcomed the US change of policy under Obama, but added the US administration must step out of the ivory tower... and not waste its and our time. Our response to Obama is clear... we welcome any change... if the US administration publicly announces its commitment to justice and respect, then the circumstances will change, he said. Three years ago, I announced that the current trend can not be continued and there must be change and fortunately the US president wants change and we welcome any real change. He said he had previously invited former US president George W. Bush to a debate and that if he was re-elected as Iranian president in next months election, he will extend the invitation to Obama.