The president’s doctors call him a “phenomenal patient” but decline to answer questions on the result of his lung scans.
Donald Trump has left the hospital after being treated for coronavirus.
He is now back at the White House after being flown there by helicopter.
Shortly before leaving the Walter Reed National Military Medical Centre in Bethesda, Maryland he tweeted: “Will be back on the Campaign Trail soon!!! The Fake News only shows the Fake Polls.”
As he left the hospital, he responded to a reporter’s question about how many people were infected at the White House by saying: “Thank you very much”.
Mr Trump’s doctors had said he was doing well enough to go home but “may not entirely be out of the woods yet”.
The president has not had a fever in more than 72 hours and his oxygen levels are normal, they added.
“He’s back” Dr Sean Conley, Mr Trump’s personal doctor, said of the president’s progress, adding that he had been a “phenomenal patient”.
The president’s medical team confirmed he had twice received extra oxygen but doesn’t now have any respiratory problems.
However, they refused to answer questions on his lung scans.
COVID-19 can cause serious damage, including pneumonia, that can be visible in such scans.
Doctors also could not say when the president would no longer be contagious or when he would be able to travel again.
Mr Trump will continue treatment at the White House, including a fifth dose of remdesivir – one of two experimental drugs he has been receiving.
Mr Trump was admitted to the hospital in Maryland on Friday, with officials saying it was just a precaution.
He went on to post several videos from inside the medical centre but a “drive-by” of supporters was criticised for potentially endangering Secret Service officers.
Dr Conley said Secret Service officers in the car during Sunday’s brief journey were wearing sufficient PPE to minimise the risk.
Mr Trump earlier on Monday sent a flurry of campaign tweets encouraging people to vote in next month’s election.
A selection of Mr Trump’s tweets earlier on Monday
He takes on Democratic candidate Joe Biden in the US election on 3 November.
Two more debates are scheduled between the pair but the effect of Mr Trump’s illness on those events is currently unclear.
The president has been criticised by many opponents for his handling of the crisis that has been linked to more than 210,000 US deaths.
Mr Trump, however, has insisted actions such as imposing travel restrictions early on in the pandemic saved thousands of lives.