The US Department of Energy has released details of a process that allows waivers for the import of low-enriched uranium from Russia if no viable alternative is available.

The move follows US president Joe Biden’s recent signing into law of legislation banning the import of Russian enriched uranium, starting a 90-day countdown until limits on shipments take effect.

The Prohibiting Russian Uranium Imports Act bars imports from Russia, but allows for temporary waivers until January 2028 if “no alternative viable source of low-enriched uranium is available to sustain the continued operation of a nuclear reactor or a United States nuclear energy company” or if the imports are determined to be in the national interest.

The DOE said then waiver process is designed to ensure US nuclear power plants do not experience disruptions.