Kiriyenko said construction of the plant was now complete.
"The construction stage of the nuclear power plant is over, we are now in the pre-comissioning stage, which is a combination of complex procedures," he told reporters.
Russia assisted Iran in the construction of the Bushehr plant in a $1bn contract, though Iran had complained of delays.
Russia attributed the delays to payment disputes, although analysts say Moscow was unhappy with Iran's resistance to international pressure to make its nuclear programme more transparent.
Iran says its nuclear programmes are for peaceful purposes. However, the West has accused Tehran of covertly attempting to develop nuclear weapons.
Russia has resisted attempts by the West to impose harsher sanctions on Iran.
However, it has also repeatedly urged Tehran to co-operate with the International Atomic Energy Agency, the UN's nuclear agency.