The Russian company that built Iran's first nuclear power station has announced that the Bushehr plant has begun running at a low level in a crucial step towards bringing it fully into operation.
Atomstroyexport said in a statement that the generating unit at Bushehr was brought up to the "minimum controllable level of power" on May 8.
Vladislav Bochkov, spokesman for Atomstroyexport's parent company Rosatom, told the media that this was "one of the final stages in the physical launch of the reactor."
The construction has faced repeated delays since the mid-1990s, when Russia reached a $1 billion deal with Tehran to finish the work which had begun in the 1970s, before the 1979 Islamic revolution.
The United States and other Western nations have urged Russia for years to abandon the project, fearing it will help Iran to develop nuclear weapons. But an agreement obliging Tehran to repatriate spent nuclear fuel to Russia has eased those concerns.