Blindsided officials are now scrambling to develop such a plan, but it is unclear when it will be announced, how or if it will be done, and whether the administration has the permanent leadership to execute it, said two administration officials.

“They are not ready for this,” a public health advocate said of an emergency declaration after talking to Health and Human Services officials enlisted in the effort.

Trump’s off-script statement stunned top agency officials, who said there is no consensus on how to implement an emergency declaration for the drug epidemic, according to interviews with officials from the White House, a half dozen federal agencies, state health directors and lobbyists.