"We keep to international law, our actions are fully legal and transparent for the International Atomic Energy Agency, and they have no complaints against us," Rumyantsev said as quoted by the Interfax news agency.
Rumyantsev is due to travel to Iran next month to discuss speeding up the construction of a nuclear plant at Bushehr, in the south of the country, a project Russia continues despite Washington's objections.
"We are building a nuclear station (in Iran), for money. This is not some kind of aid, this is a commercial project," Rumyantsev declared.
Non-proliferation of nuclear materials and technologies as well as nuclear security would be the main topic at the meeting, Rumyantsev said.
Nevertheless Russia's nuclear cooperation with Iran is high up on the agenda of Rumyantsev's talks with Bolton, a prospect Rumyantsev viewed with some humor.
"I always say that if we did not talk about Iran, it's as if we haven't met," the minister commented.
Uranium enrichment is at the centre of international concern that Iran may be capable of building an atomic bomb. Tehran has said it reserves the right to restart enrichment "at any moment."
Russia has made completion of the Bushehr nuclear plant conditional on Iran signing an undertaking to return the spent fuel.
Russia has overridden strong objections from the United States to maintain its nuclear cooperation with Iran.