The weekly mass participation Parkrun events have been suspended across the United Kingdom because of the coronavirus pandemic.
Organisers say the closure will be in place initially until the end of March, but is likely to continue into April.
The movement was founded in Bushy Park, London in 2002 by Paul Sinton-Hewitt and is now in 20 countries.
There are 715 different locations across the UK staging the weekly events and more than two million runners.
Events in 17 countries had already been called off, but the UK has now been added to the list, meaning there will be no Parkruns across the world for at least the next two weeks.
Parkrun chief operating officer Tom Williams said: "We know that this message may be a difficult one for you to receive, Rest assured that we are working hard to develop our strategy so that we are able to support the health and happiness of parkrunners around the world during this difficult time.
"Remaining active is incredibly important, and we are working on ways to encourage and support that."