Iran's foreign minister on Thursday brushed aside demands from the seven major industrialized nations and Russia to respond by July 5 to an international offer for Tehran to roll back its uranium enrichment program, saying his nation would need until August.Foreign Minister Manouchehr Mottaki said Iran had questions about the proposal that will be raised in talks expected early next month with Javier Solana, the European Union's foreign policy chief. The questions need to be answered so Tehran can respond in August, he said.Mottaki's remarks contradicted his own statements published Wednesday in the German weekly magazine Stern, which quoted him as saying his country may respond before the Group of Eight summit in St. Petersburg, Russia, which starts July 15.Earlier Thursday, The United States, Russia and other industrialized democracies said they want Iran to answer "yes" or "no" next week to an international offer to bargain over Teheran's disputed nuclear program, and said they are disappointed the regime has not replied by now."We are disappointed in the absence of an official Iranian response to this positive proposal," said a statement from foreign ministers of the Group of Eight industrial nations. "We expect to hear a clear and substantive Iranian response to these proposals" at a meeting scheduled July 5 between the European Union's foreign policy chief and Iran's nuclear negotiator Ali Larijani.That meeting between Larijani and the EU's Javier Solana would be the first since the EU official presented the incentive package to the Iranian negotiator in Tehran on June 6.Larijani said then that the proposals contained "positive steps" but that talks were needed to clear up ambiguities.The diplomats on Wednesday called Teheran's nuclear program "a source of international concern," and endorsed the offer to Iran to accept economic incentives in return for giving up disputed aspects of the program, which Tehran claims is peaceful."An agreement of this sort would allow the Iranian people to enjoy the benefits of modern civil nuclear power and would bring Iran many other long-term political and economic advantages," the G-8 ministers' statement said.Russian Foreign Minister Sergey Lavrov said the six major nations involved in negotiating with Teheran will assess the Iran situation by mid-July.G8 foreign ministers were meeting in Moscow before a July 15-17 summit of G8 leaders, to be held in St. Petersburg and hosted for the first time by Russian President Vladimir Putin.The ministers also discussed world hotspots including Israel and the West Bank, North Korea, Iraq, Afghanistan and the Balkans.