According to the U.S. State Department, Iran has no known heavy water reactor (aside from a small IAEA-safeguarded “zero-power” research reactor located at the Esfahan Nuclear Technology Center) and no need for an indigenous source of heavy water. Iran’s only nuclear power reactor expected to become operational within the next decade is the light-water reactor under construction with Russian help at Bushehr. This raises serious questions about Iran’s intentions in constructing an industrial-scale heavy water production plant at Arak. Heavy-water moderated reactors are better suited for plutonium production than are light water reactors. Thus, the State Department said in May 2003 that it believes Iran’s true intent is to develop the capability to produce fissile material for nuclear weapons, using both the plutonium route (supported ultimately by a heavy-water research reactor) and the highly enriched uranium route (supported by a gas centrifuge enrichment plant).