He said in a public health order: “If COVID-19 were detected at these festivals, the scope and number of attendees and the nature of the venue would make it infeasible, if not impossible, to track those who may be placed at risk.”
On Friday, health officials in California announced the state had surpassed 40,000 coronavirus-related deaths.
Goldenvoice, which organises both Coachella and Stagecoach, has been contacted for comment.
This is the third time Coachella has shifted due to the health crisis.
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In March last year organisers pushed the festival, which was set to be headlined by Travis Scott, Frank Ocean and Rage Against the Machine, from April to October, before those dates were also cancelled with the virus still raging across the US.
The Coachella Valley Music and Arts Festival takes place in the Indio desert near Palm Springs and attracted about 250,000 attendees in 2019, while Stagecoach draws more than 70,000 country music fans.