The spokesman said that loading the reactor with fuel would be a key step towards starting up the reactor at the Islamic Republic's first nuclear power plant, though the reactor would not be considered operational from that date.
"The fuel will be loaded on August 21," Rosatom spokesmen Sergei Novikov said by telephone. "This is the start of the physical launch (of the reactor)."
ITAR-TASS news agency reported earlier that the reactor would be started up on August 21, citing a statement posted on the website operated by Russia's state nuclear corporation.
The statement was soon withdrawn from the site and no correction was immediately issued.
Prime Minister Vladimir Putin said on March 18 that Russia planned to start up the reactor at the Bushehr plant in the summer of 2010.
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