The US now has more confirmed cases of coronavirus than any other country with at least 82,404 positive tests.
According to the latest figures collated by Johns Hopkins University, the US overtook China (81,782 cases) and Italy (80,589).
More than 1,100 people with Covid-19 have died in the US.
At a White House briefing on Thursday afternoon, Mr Trump said: "They have to go back to work, our country has to go back, our country is based on that and I think it's going to happen pretty quickly.
"We may take sections of our country, we may take large sections of our country that aren't so seriously affected and we may do it that way."
He added: "A lot of people misinterpret when I say go back, they're going to be practising as much as you can social distancing, and washing your hands and not shaking hands and all of the things we talked about."
In a letter to state governors on Thursday, Mr Trump said his team plans to release federal social distancing guidelines that may advise some regions to loosen restrictions.
Mr Trump wrote of a "long battle ahead" and said "robust" testing protocols might allow some counties to lift their safeguards against the coronavirus.



He said the "new guidelines" will create low, medium and high risk zones that will allow the government to advise on "maintaining, increasing, or relaxing social distancing and other mitigation measures they have put in place".
Earlier this month, he set a 15-day period to slow down the spread of Covid-19 by urging all Americans to drastically scale back their public interactions during this time.
But the guidelines were voluntary and did not amount to a national order. Mr Trump has set a goal of Easter Sunday, 12 April, for reopening the country.
But the US Constitution makes clear states have the power for maintaining public order and safety, which scholars say means it is the responsibility of governors to decide when virus-related restrictions get lifted.
Currently 21 US states have told residents to stay in their homes in order to contain the pandemic.
The US president has used federal powers to tackle the outbreak, such as the Stafford Act, which has unlocked tens of billions of dollars in emergency aid.
Canada has condemned a US proposal to deploy troops along their joint border to help fight the spread of coronavirus, with the deputy prime minister saying it would be an "entirely unnecessary step which we would view as damaging to our relationship"
A supermarket in Pennsylvania said it had to destroy more than $35,000 worth of food after a woman intentionally coughed all over it in a coronavirus prank. The local prosecutor said it would decide whether or not to press charges once the suspect had been tested for the illness.
According to the San Francisco Chronicle, coyotes are being seen roaming the empty streets of the California city, where residents have withdrawn behind closed doors to limit the spread of the virus