The coronavirus task force’s leading public health expert, Dr Anthony Fauci, said there is light at the end of the tunnel, with a rolling entry for less-affected areas reopening before places like New York that are in a “really difficult situation”.

While not naming a specific state that could reopen before 1 May, Dr Fauci said on Tuesday night that, while he hadn’t spoken directly with Donald Trump, the president was discussing states with a low density, a lot of land and low levels of infection.

At his daily press briefing on Tuesday, Mr Trump said he would authorise governors to implement reopenings at a time most appropriate for their states, and that he would support the easing of restrictions in some states before federal guidelines on social distancing end on 30 April.

When asked which states would be ready to reopen before 1 May, Dr Fauci said he hasn’t “gone through state by state”.

“There is going to be a great deal of variability,” Dr Fauci said. “There probably would be a rolling entry into it with some states actually doing nothing different because they’re still in a really difficult situation and you would not want to relax any of the physical separation guidelines and others that would be doing really much better. So it’s not going to be a one size fits all.”

Earlier, Dr Fauci told the Associated Press that, ultimately, the virus would determine when the country can safely reopen, both in general and in specific locations.

Dr Fauci, who was absent from Tuesday evening’s White House press conference and appeared on an NBC primetime special, said that juggling the response to the virus while also appearing at Mr Trump’s daily briefings was “draining”.

“Being there to be able to answer the questions of media I think is really important, because we’re going through a real public health crisis in our country,” Dr Fauci told the AP.

“The downtime that we have there is really draining. You know you wait around for it to start, you prepare for it to start, you stand and you get up. Like last night I got home at, I must have been about 9 o’clock.

“If I had been able to just make a few comments and then go to work that would have really been much better. But it’s the downtime.”

During the NBC broadcast, Dr Fauci said that to safely reopen across the country, health experts would need to be able to identify, isolate, get out of circulation and do contact tracing as new cases arise.

He said that they’re developing the capability of escalating test production so that they could conduct millions of tests each week, saying the real proof of success would be how quickly and effectively they could identify people that have contracted the Covid-19 infection.

“Right now given what we are doing, the worst looks like, for the most part, with a couple of exceptions, there’s still a couple of cities right now that we’re worried about that haven’t yet peaked and turned around,” he said.

“But if you look at the New York metropolitan area as kind of the prototype that’s been driving this through the country, and then look at the country as a whole, there’s no doubt that what we’ve seen over the last several days is a flattening out, and even when you get to New York it’s actually starting to come down regarding admissions, hospitalisations, need for intensive care and intubation. Hopefully, that trend will continue.

“So as I say, I’m a very cautious person but we are seeing some light at the end of the tunnel.”