For years, the federal government has been working on turning old, unexploded warheads left over from the Cold War into a fuel for next-generation nuclear power plants. Now, a significant new deal in the works could allow five private companies to access weapons-grade plutonium for the first time — and convert it into electricity.

The Trump administration is reportedly in talks with five companies to provide old plutonium to convert into fuel for future nuclear reactors.

Companies say it’s a better way to dispose of the Cold War-era material — and fix a shortage of nuclear fuel. But the plan has also faced criticism.