The U.S. Energy Department's Advanced Research Projects Agency-Energy, or ARPA-E, aims to develop a dozen projects to recycle spent nuclear fuel.
"I don't see many really looking seriously into reprocessing," Grossi told Reuters in an interview late on Wednesday at the COP27 climate summit in Egypt.
Former U.S. President Jimmy Carter had halted reprocessing of nuclear waste in 1977, citing proliferation concerns.
"Nobody will be doing reprocessing without the IAEA being involved," he said, noting that any nuclear waste recycling North Korea is undertaking is an exception.
The United States has spent billions of dollars over decades on a project at Yucca Mountain in Nevada to store nuclear waste.