On Tuesday, a Ukrainian representative at a nuclear security summit in The Hague accused Russia of threatening the security of nuclear reactors in Ukraine and called on the world to help protect them.

The Russian Foreign Ministry dismissed the allegations as an attempt to redirect blame for ongoing instability in the country away from the new Ukrainian government.

The ministry said Russia continues to fulfill its obligations to Ukraine by supplying nuclear fuel and helping to maintain nuclear security in the country, where 15 nuclear reactors are currently in operation, according to the International Atomic Energy Agency.

Kiriyenko said Thursday that Rosatom's international contracts may be impacted by economic sanctions, but such an eventuality was highly unlikely in practice as nuclear contracts are usually long-term.

"Taking into account a wide range of comments on possible limitations in economic cooperation, we understand that some of these [international] contracts may be limited by politics," he said.

"We are committed to long-term cooperation with our partners. As of today, our plans remain unchanged and none of our contracts have been terminated."

As of March, Rosatom has construction orders for 22 nuclear power units on the books, and talks on many more were underway.

Hours after imposing sanctions on dozens of Russian officials and lawmakers on March 20, US President Barack Obama threatened Moscow with more sanctions targeting key sectors of its economy, such as energy, finance, defense and heavy industry.

Russia's Foreign Ministry earlier said that talking to Russia in the language of sanctions is "inappropriate and counterproductive" and warned its Western partners about the "boomerang effect" that sanctions would have on the West.