[h=1]U.S., China, Russia make Iran pledge[/h] HONOLULU -- President Obama said Saturday that he and the leaders of two other key nuclear powers -- Russia and China -- will work together to combat the development of nuclear weapons by Iran. Meeting at the Asian-Pacific Economic Cooperation summit here, he and Russian President Dmitry Medvedev "reaffirmed our intention to work and shape a common response so we can move Iran to follow its international obligations when it comes to its nuclear program,"â€ Obama said. After a second meeting, with Chinese President Hu Jintao, Obama said that the United States and China both want to ensure that Iran sticks to "international rules and norms" about its alleged secret work to build nuclear weapons. The International Atomic Energy Agency warned in a report released this week that Iranian scientists have made significant progress toward developing nuclear weapons, though the government in Tehran has countered that its nuclear program is exclusively for energy production and research. Obama thanked Medvedev for "several years of constructive engagement" with the United States, including the 2010 START arms control treaty and Russiaâ€™s plans to join the World Trade Organization. Medvedev said that Russia had not received the same levels of support from previous U.S. administrations and said that U.S.-Russian collaboration is good for trade around the world. But the Russian president said that the two countries continue to work toward an agreement on arms control, though "we understand that our positions remain far apart." On a lighter note, Obama noted that Medvedev was spotted around Honolulu wearing a Hawaiian shirt. The president said he was glad his Russian counterpart was enjoying himself.