Each person non resident of the Russian Federation prior to applying for visa in the consulate must get an invitation according to the purpose of his or her visit.
Your Visa To Russia provides invitations for tourist and business trips.

Bushehr nuclear saga enters final chapter

Russia is to start loading fuel into the reactor at Iran’s first nuclear power plant – a key step in making the Bushehr station operational. But what is the project about? Purely business, or an ace in a political hand?

All Russia news »

Source: http://rt.com/Politics/2010-08-20/bushehr-plant-launch-iran.html