LOS ANGELES • California's Governor Gavin Newsom has ordered all residents in the state to wear face masks in public, in a bid to stem the spread of the coronavirus.
"Science shows that face coverings and masks work," Mr Newsom said in a statement on Thursday. "They are critical to keeping those who are around you safe, keeping businesses open and restarting our economy."
This comes after a decision last week by officials in Orange County, south of Los Angeles, to rescind an order requiring people to wear masks in public.
Three other counties - Fresno, Riverside and San Bernardino - had also walked back on requirements to wear face coverings because of public pressure.
"Simply put, we are seeing too many people with faces uncovered - putting at risk the real progress we have made in fighting the disease," Mr Newsom said. "California's strategy to restart the economy and get people back to work will only be successful if people act safely and follow health recommendations."
Studies worldwide have shown that wearing face coverings cuts the risk of spreading Covid-19.
However, wearing a face mask in many parts of the United States has increasingly taken on a political dimension.
For many on the right, wearing a mask is seen as bowing to government authority, while on the left it is seen as beneficial to limiting the spread of the virus.
Mr Newsom in mid-March became the first governor in the US to issue a stay-at-home order and subsequently left it up to the state's counties and cities to decide on whether to maintain the order as well as requirements on face coverings and other curbs.
The issue set off a firestorm of controversy in Orange County, once a bastion of Republican politics, where some residents and local officials challenged an order to wear face coverings while in public, at work or a business where social distancing is not possible.
The county's health officer, Dr Nichole Quick, resigned last week after coming under scathing criticism and having a poster depicting her with a Hitler moustache.
She was also given a security detail after receiving a death threat.
Under Mr Newsom's statewide order, Californians or visitors must wear face coverings in any indoor public space, while using public transport, in a taxi or in a ride-sharing vehicle. They must also be masked while at work or outdoors in public spaces.
Children two and under are exempt as are people with medical or mental health concerns or developmental disabilities that prevent them from wearing a face covering.