President Donald Trump has claimed “total” power to lift the nationwide coronavirus lockdown, contradicting governors and legal experts.
“The president of the United States calls the shots,” Mr Trump said during a combative press conference in which he feuded with reporters.
But the US Constitution says the states maintain public order and safety.
Ten states on the US East and West coasts are planning to lift their strict stay-at-home orders.
The US is the global epicentre of the coronavirus pandemic with 554,684 confirmed cases and 23,608 deaths.
Mr Trump, a Republican, told the daily White House coronavirus briefing on Monday that his administration was finalising a plan to reopen the US economy, which has been largely shut down to slow the spread of the coronavirus.
The Trump administration has signalled 1 May as a potential date for easing the restrictions.
The current White House recommendations for Americans to avoid restaurants and non-essential travel and keep in-person gatherings to no more than 10 people expire on 30 April.
But when journalists queried whether Mr Trump had the authority to over-ride stay-at-home orders imposed on a state-by-state basis, he said: “When somebody is the president of the United States, the authority is total.