The United States expects Russia's next president, Dmitry Medvedev, and his promised prime minister, current President Vladimir Putin, to be guided by the Russian constitution in the way they run the government. State Department spokesman Tom Casey was asked Monday whether the United States expects Putin to be the power behind the throne after Medvedev publicly assumes power. "I expect that President Medvedev will be president of Russia (and) that if, in fact, as he's indicated, he will name President Putin his prime minister, that he will fulfill those duties," Casey said. "The Russian system has a pretty clear delineation of responsibilities between the president and prime minister," Casey said. "Until proven otherwise, I think we'll expect that those officeholders will carry out their duties and responsibilities in accordance with the constitution."