Shares in uranium miners jumped globally after the US said it’s soliciting bids to boost domestic production of nuclear fuel in an effort to bolster national energy security.

The Energy Department is requesting proposals from US companies to produce a type of fuel known as high-assay low-enriched uranium, or HALEU, it said Tuesday. It plans to invest as much as $500-million in the projects and other ventures to convert HALEU into chemical precursors for nuclear fuels.

North American uranium miners including Global Atomic and NexGen Energy rose after the announcement, while peers in Australia including Paladin Energy and Deep Yellow increased sharply Wednesday on prospects for higher prices. Uranium investment firm Yellow Cake climbed to a record as trading opened in London, extending last year’s 65% gain.

The Biden administration is intensifying efforts to ramp up enrichment after the US House voted to approve legislation that would bar enriched-uranium imports from Russia, the country’s top foreign supplier. Although it has been held up in the Senate — and would only enter effect later this decade if turned into law — the bill has given fresh impetus to a rebound in prices for raw nuclear fuel.

Bloomberg reported last month that Tenex, a Russian state-owned uranium company, had warned American customers that the Kremlin may preemptively bar exports of its nuclear fuel if lawmakers in Washington passed the legislation. Parent company Rosatom denied that Tenex had done so.

Futures tracking spot prices for a raw form of uranium known as yellowcake hit a 15-year high Tuesday. They more than doubled last year as Western efforts to boost energy security and cut emissions sparked a global nuclear renaissance.

“The global pivot back to nuclear energy creates opportunities and challenges,” John Ciampaglia, CEO of Sprott Asset Management, said earlier this month. “We need to rebuild supply chains that have long since disappeared.”

To be sure, soaring development costs have left prospective producers in a precarious position, with NuScale Power Corp. — the first company with US approval for a small nuclear reactor design — canceling plans to build a power plant in November. It fired more than a quarter of its staff this month.

One of the promises of smaller reactors is that they’re supposed to be easier to build, limiting cost overruns and delays that have commonly plagued the development of conventional large-scale reactors. A massive new Southern Co. nuclear plant in Georgia entered service in July, seven years late and with a budget that more than doubled to over $30-billion.