LONDON (Reuters) - British Prime Minister Boris Johnson was admitted to hospital for tests on Sunday in what Downing Street said was a "precautionary step" because he was showing persistent symptoms of the coronavirus 10 days after testing positive for it.

Below is a timeline with what we know about his activities over those 10 days, when he was self-isolating but still leading Britain's response to the coronavirus outbreak, including chairing daily virtual emergency meetings.

March 27, Friday - Johnson said he had tested positive for the coronavirus and that he would self-isolate in Downing Street. Health Minister Matt Hancock also tested positive, while England's top medical officer began self-isolating after developing symptoms.

"I've developed mild symptoms of the coronavirus. That's to say - a temperature and a persistent cough," Johnson said in a video posted on Twitter.

"Be in no doubt that I can continue, thanks to the wizardry of modern technology, to communicate with all my top team to lead the national fightback against coronavirus."

Johnson spoke by phone to U.S. President Donald Trump, who wished him a speedy recovery.

Johnson chaired a government meeting on the coronavirus on Friday morning via teleconference. Johnson had meals delivered to the door of an apartment at 11 Downing Street while in self-isolation.

March 28, Saturday - It is announced that Johnson will write to every UK household urging people to stay at home to help contain the coronavirus.

March 29, Sunday - Johnson posted a video of himself in a suit and tie, thanking people for staying at home as well as health workers, grocers and pharmacists.

March 30, Monday - Foreign Secretary Dominic Raab said Johnson was "full of vigour" despite being self-isolated. Johnson's spokesman said that Johnson was fully able to run Britain's coronavirus response despite the positive test, and he continued to chair daily meetings.

Johnson tweeted a picture of himself attending a meeting via video link.

March 31, Tuesday - Johnson chaired Cabinet - the first all-digital meeting of a British PM's top team of ministers - on video platform Zoom.

April 1, Wednesday - Johnson posted a video message on Twitter, lamenting a rise in the number of coronavirus-related deaths in Britain.

April 2, Thursday - In another video message, Johnson vowed to ramp up testing for the coronavirus.

He also came out by himself onto the doorstep in Downing Street to applaud frontline medical workers as part of the "Clap For Carers" initiative.

April 3, Friday - A weary-looking Johnson said he would remain in isolation as he continued to have mild symptoms of COVID-19, the respiratory disease caused by the novel coronavirus, including a high temperature, a week after he tested positive for the virus.

"Although I'm feeling better and I've done my seven days of isolation, alas I still have one of the symptoms, a minor symptom, I still have a temperature, so in accordance with government advice I must continue my self-isolation until that symptom itself goes," Johnson said in a video message, wearing an open-necked shirt.

April 4, Saturday - Johnson said in a tweet that he spoke to newly elected opposition Labour leader Keir Starmer and invited him and other party leaders to a briefing the following week on how to work together during the national emergency.

April 5, Sunday - Downing Street announced in the evening that Johnson had been taken to hospital as a precautionary measure because of the persistent nature of his symptoms 10 days after he first tested positive.

(Reporting by Alistair Smout and Mark Bendeich; Editing by Peter Cooney)