WASHINGTON — US President Donald Trump’s National Security Adviser Robert O’Brien has tested positive for the coronavirus, according to Bloomberg. O’Brien is the most senior official in the Trump administration to become infected with COVID-19, it said citing sources familiar with the matter. O’Brien contracted coronavirus after a family event, who said he “has been isolating at home while still running the National Security Council.” He has been doing the majority of his work by phone, Bloomberg added. O'Brien recently returned from Europe, where he and his top deputy met with officials from the UK, France, Germany and Italy. A senior administration official said O'Brien has been working from home since last week. A source familiar said O'Brien was last in the office last Thursday, when he abruptly left the White House. The White House statement said there is no risk of exposure to the president or the vice president. The National Security Council chief was accompanied on the trip to Europe by Secret Service agents, staffers and multiple reporters. Multiple pictures released from the trip showed O'Brien neither practicing social distancing nor wearing a mask. One of Trump’s personal valets, who works on the White House grounds, tested positive for coronavirus in May. Trump and Vice President Mike Pence are regularly given tests for the coronavirus. — Agencies