WASHINGTON, Sept. 26 (Xinhua) -- U.S. President Barack Obama on Saturday reiterated his call for Iran to have "a serious, meaningful dialogue" over its disputed nuclear program.

"Iran's leaders must now choose - they can live up to their responsibilities and achieve integration with the community of nations, or they will face increased pressure and isolation, and deny opportunity to their own people," Obama said in his radio address.

U.S. President Barack Obama speaks about the results of the G20 Summit at a post summit news conference after the conclusion of the summit in the Pittsburgh Convention Center in Pittsburgh, Pennsylvania, Sept. 25, 2009

"Iran must now cooperate fully with the International Atomic Energy Agency, and take action to demonstrate its peaceful intentions," Obama said.

    An international talk with Iran is due to be held in Geneva on Oct. 1. Officials from six world powers - the United States, Britain, France, Russia, China and Germany - will participate in the discussions.

    The Obama administration has insisted that the scheduled meeting must address Iran's nuclear issue.

    However, Iranian President Mahmoud Ahmadinejad said that discussions on the nuclear issue were "finished." He said that Iran will make no compromise with the West over its nuclear program.