TEHRAN (AFP) - Iranian President Mahmoud Ahmadinejad said on Tuesday that the world's major powers were in decline and that developing countries could play a greater role in resolving world conflicts. "The great powers are in the process of decline. Their influence is waning. They have reached the end of their era, we are at the threshold of a new era," Ahmadinejad told a ministerial meeting of the Non-Aligned Movement in Tehran. "Pious and chaste powers should take the lead in the world," he added in a speech to foreign ministers at the meeting of the 118-member movement. "The NAM... can play a prominent role in current global challenges and compensate for the lack of efficiency in international bodies," His comments come amid a standoff between Iran and the international community over Tehran's nuclear drive, which some Western nations say could be a cover for plans to built atomic weapons. Iran is under three sets of UN Security Council sanctions over its refusal to halt uranium enrichment, a process which makes nuclear fuel but can also create the fissile core of an atomic bomb. NAM states consider themselves not formally aligned with or against any major power bloc. "By using political and economic tools, (the NAM) should prevent any aggression by big powers against other nations and stand up against discrimination and injustice," Ahmadinejad said. "It should exert efforts to reform the international political, economic and social systems. "Today the NAM more than ever can use its unique position to solve world problems, compensate for the inefficiency of international organisations and call for peace and justice in the world." Cuban Foreign Minister Felipe Perez Roque called for the movement to have a greater role in the UN Security council, with a right of veto. "We should strengthen the role of NAM in the UN Security Council in order to help establish durable peace and security at the international level," he said, according to the official IRNA news agency.