A Downing Street spokeswoman said: “After experiencing mild symptoms yesterday, the Prime Minister was tested for coronavirus on the personal advice of England’s Chief Medical Officer, Professor Chris Whitty.
“The test was carried out in No 10 by NHS staff and the result of the test was positive.
“In keeping with the guidance, the Prime Minister is self-isolating in Downing Street.
“He is continuing to lead the government’s response to coronavirus.”
Updates to follow.
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Donald Trump and Boris Johnson
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Donald Trump and Boris Johnson
British Prime Minister Boris Johnson, right, and U.S. President Donald Trump pose during a group photo during a NATO leaders meeting at The Grove hotel and resort in Watford, Hertfordshire, England, Wednesday, Dec. 4, 2019. NATO Secretary-General Jens Stoltenberg rejected Wednesday French criticism that the military alliance is suffering from brain death, and insisted that the organization is adapting to modern challenges. (Peter Nicholls, Pool Photo via AP)
British Prime Minister Boris Johnson, left, reaches out to shake hands with U.S. President Donald Trump at the official arrivals for a NATO leaders meeting at The Grove hotel and resort in Watford, Hertfordshire, England, Wednesday, Dec. 4, 2019. NATO Secretary-General Jens Stoltenberg rejected Wednesday French criticism that the military alliance is suffering from brain death, and insisted that the organization is adapting to modern challenges. (AP Photo/Francisco Seco)
British Prime Minister Boris Johnson walks over to U.S. President Donald Trump who is talking to Canadian Prime Minister Justin Trudeau prior to a NATO leaders meeting at The Grove hotel and resort in Watford, Hertfordshire, England, Wednesday, Dec. 4, 2019. As NATO leaders meet and show that the world's biggest security alliance is adapting to modern threats, NATO Secretary-General Jens Stoltenberg is refusing to concede that the future of the 29-member alliance is under a cloud. (AP Photo/Frank Augstein)
British Prime Minister Boris Johnson, right, and U.S. President Donald Trump pose during a group photo during a NATO leaders meeting at The Grove hotel and resort in Watford, Hertfordshire, England, Wednesday, Dec. 4, 2019. NATO Secretary-General Jens Stoltenberg rejected Wednesday French criticism that the military alliance is suffering from brain death, and insisted that the organization is adapting to modern challenges. (Peter Nicholls, Pool Photo via AP)
President Donald Trump meets with British Prime Minister Boris Johnson at the United Nations General Assembly, Tuesday, Sept. 24, 2019, in New York. In a decision with wide-ranging political ramifications, Britain's Supreme Court plans to give its verdict Tuesday on the legality of Prime Minister Boris Johnson's five-week suspension of Parliament. (AP Photo/Evan Vucci)
President Donald Trump meets with British Prime Minister Boris Johnson at the United Nations General Assembly, Tuesday, Sept. 24, 2019, in New York. (AP Photo/Evan Vucci)
President Donald Trump meets with British Prime Minister Boris Johnson at the United Nations General Assembly, Tuesday, Sept. 24, 2019, in New York. (AP Photo/Evan Vucci)
President Donald Trump meets with British Prime Minister Boris Johnson at the United Nations General Assembly, Tuesday, Sept. 24, 2019, in New York. (AP Photo/Evan Vucci)
U.S. President Donald Trump, left, and Britain's Prime Minister Boris Johnson attend a working breakfast at the Hotel du Palais on the sidelines of the G-7 summit in Biarritz, France, Sunday, Aug. 25, 2019. (AP Photo/Andrew Harnik)
President Donald Trump and Britain's Prime Minister Boris Johnson, left, speak to the media before a working breakfast meeting at the Hotel du Palais on the sidelines of the G-7 summit in Biarritz, France, Sunday, Aug. 25, 2019. (Erin Schaff, The New York Times, Pool)
FILE - In this Aug. 25, 2019, file photo, President Donald Trump and Britain's Prime Minister Boris Johnson, left, speak to the media before a working breakfast meeting at the Hotel du Palais on the sidelines of the G-7 summit in Biarritz, France. Johnson says he’ll tell President Donald Trump that the U.K.’s state-funded health service will be off the table in any future trade negotiations, and that the U.S. will have to open its markets to British goods if it wants to make a deal. (Erin Schaff/The New York Times, Pool, File)
