President Joe Biden on Monday signed legislation banning the import of Russian enriched uranium, starting a 90-day countdown until limits on shipments of the reactor fuel take effect. 

Biden’s signature also unlocks some $2.7 billion in spending, previously approved by Congress, to build up domestic uranium supplies for US nuclear plants. That money was contingent on the federal government imposing limits on Russian uranium imports.

The move, which comes as Russia’s invasion of Ukraine grinds into its third year, carries risks. Russia is America’s top foreign source of the fuel, supplying about a quarter of the uranium used in US reactors, according to Energy Department data. Russia makes about $1 billion a year from those sales. Cutting off that supply could raise uranium prices 20%, according to Jonathan Hinze, president of nuclear fuel market research firm UxC.

President Joe Biden

But the legislation lets the Energy Department issue waivers allowing the import of Russian enriched uranium until 2028 if no alternative source is found or if the imports are determined to be in the national interest. 

There’s also the possibility Russia could retaliate. In December Tenex, a Russian state-owned uranium supplier, warned American customers that the Kremlin might preemptively bar exports of its nuclear fuel to the US if lawmakers imposed a ban.

Fletcher T. Newton, president of Tenex-USA, Inc. said in an interview the company “fully intends to honor all of their contractual commitments in the United States.” But Tenex, he said, has no control over whatever action the Kremlin might take.

US nuclear plant owners have been planning for a ban. A spokesman for Constellation, the largest U.S. nuclear plant operator, said the company has worked with suppliers to secure enough fuel to power their operations into 2029, with contracts extending beyond then. 

But analysts say there may still be smaller plant operators that haven’t fully prepared for the disruption. And fuel supplier Centrus Energy Corp., which is based in the US but relies on Tenex for the majority of the uranium it delivers, warned in its most recent annual report that a ban would pose “a significant risk” to the business. 

“While we have other sources, they are not sufficient to replace the Tenex supply,” the report said. The company plans to apply for waivers. 

The US was once a leading supplier of enriched uranium but lost its edge in the industry decades ago. The country now has just one commercial enrichment facility in New Mexico, owned by Urenco Ltd., a British, Dutch and German consortium. Centrus, based in Bethesda, Maryland, began production in October at a pilot project in Piketon, Ohio, and eventually expects the site to supply as much as 900 kilograms a year of specialized, highly enriched reactor fuel to be used in a new breed of advanced reactors. 

Centrus also has secured approximately $900 million in conditional sales commitments to support a plan to produce conventional, low-enriched uranium reactor fuel, Chief Executive Officer Amir Vexler said Wednesday on an earning call. The company intends to compete for billions of dollars in funding the Energy Department will make available to support domestic enrichment, he said.

The Energy Department plans to use the $2.7 billion to help rebuild the domestic supply chain by creating a guaranteed buyer of American-made reactor fuel. Companies that could benefit from the spending include ConverDyn, a joint venture between Honeywell International Inc. and General Atomics that provides uranium conversion services, and Global Laser Enrichment, owned jointly by Silex Systems LTD and and Cameco Corp.

“To reduce – and ultimately eliminate – our current dependence on Russian uranium for civilian nuclear power reactors, the most important step the US government can take is to invest in US commercial enrichment,” the White House National Security Council said in a statement.