Vienna (AFP) - Iran and world powers have given themselves seven more months to clinch a landmark nuclear agreement, and defuse a 12-year standoff, after missing a Monday midnight deadline for a deal.The failure came despite an intensive five-day diplomatic push in the Austrian capital Vienna involving the foreign ministers of Iran, the United States, Russia, China, Britain, France and Germany.But US Secretary of State John Kerry, speaking in Vienna, and Iranian President Hassan Rouhani, speaking in Tehran, said real progress had been made in the talks and raised hopes a deal could eventually be sealed."This path of negotiation will reach a final agreement," Rouhani said on state television.