despite ongoing concerns from the united nations. engineers from iran and russia loading fuel into the country's first nuclear power plant. with iran still insisting it only has interest in energy production. and the russians saying, they'll make sure the facility is not used to make weapons. fox's caroline shively has the latest developments from washington. so, caroline, the big question of the day is, why should we believe that iran, when they say that this plant isn't being used to make weapons? >> well, for one thing, kelly the international atommic energy agency is there and watching them when they bring in the fuel rods and don't divert them to use for a bomb. a capability question. you need to enrich more than 90% for a nuclear weapon. this new plan is set to 3 1/2% and iran has a pilot program that enriches it to 20% for a medical research reactor. take a listen to one iranian official. >> we had said this over and over, that we are not