Iran has confirmed it has been forced to begin removing fuel from its nuclear reactor at the southern city of Bushehr, citing “safety reasons” but providing few other details. The move adds another delay to the startup for the reactor, which was to produce electricity for the nation by January, but which missed its first deadline.

Iranian nuclear envoy Ali Asghar Soltanieh told the ISNA news agency the fuel was being ejected from the core of the reactor so that tests could be conducted.

The Russian engineers involved in the construction of the plant had advised the move, he said. “Based on Russia's request to run tests and technical measures, the fuel will be unloaded from the core of the reactor and will be returned to it after completion of the experiments and technical work,” Soltanieh said.

The process of unloading the fuel from the reactor could take up to six days, according to a source close to the project quoted by Reuters.

The International Atomic Energy Agency (IAEA) is to supervise the process, Soltanieh said.