The orders grant the U.S. Energy secretary authority to approve advanced reactor designs and projects, taking authority away from the independent safety agency that has regulated the U.S. nuclear industry for five decades.

Among a flurry of executive actions, Mr. Trump directed the nation’s nuclear safety regulator to speed up approvals for new reactors.

Facing the first rise in power demand in two decades from the boom in artificial intelligence, Trump declared an energy emergency on his first day in office. Chris Wright, the energy secretary, has said the race to develop power sources and data centers needed for AI is "Manhattan Project 2",