He later announced he and his wife had tested negative for the virus.
It was announced yesterday the president and his wife had tested positive for Covid-19.
Today, Trump was taken to a military hospital as he battles "fatigue" and a fever after the Covid-19 diagnosis.
He has been treated with Regeneron, an antibody cocktail.
The president's children - Barron, who lives with his parents at the White House, and Ivanka Trump - have tested negative.
Officials say there are 11 cases related to the setup and planning of Tuesday's presidential debate.
The US president's positive test comes a month before Americans go to the polls after an election campaign marked by Trump's downplaying of the pandemic.
Trump's diagnosis has sparked fears of a destabilising effect in Washington and around the world.
- In addition with AP