Donald Trump's national security adviser has tested positive for coronavirus.
Robert O'Brien has been isolating and working from home after contracting the virus at a family event, Bloomberg reports.
Mr O'Brien has mild symptoms and there is no risk of exposure to the US president, the White House said.
"He has mild symptoms and has been self-isolating and working from a secure location off site," a statement said.
"There is no risk of exposure to the President or the Vice President.
"The work of the National Security Council continues uninterrupted."
Mr O'Brien is reportedly doing most of his work by phone.
White House staff are regularly tested for the virus and Mr O'Brien is the most senior official to have tested positive during the pandemic.
A US military member who works at the White House as a valet tested positive for coronavirus in May, as well as Vice President Mike Pence's press secretary.
The United States has more than 4.2 million confirmed coronavirus cases and nearly 147,000 have died after contracting the virus.
