Telling everyone to wear face masks in public could put the supply to frontline staff at risk, hospital leaders have said.
Wearing masks is compulsory on public transport and in shops in Austria, Czech Republic, Slovakia and New York.
And the London mayor Sadiq Kahn has said the capital should follow suit.
The government is carrying out a review into the usefulness of masks in preventing the spread of infection, despite the World Health Organisation (WHO) saying there is no evidence to support their use by the general population.
And Chris Hopson, chief executive of NHS Providers, has asked the government to make sure the impact on hospitals of any change in advice is fully assessed.
In a statement he said: "Fluid repellent masks for health and care staff are key to safety and to avoid the spread of coronavirus.
"Securing the supply of masks, when there is huge global demand, is crucial. This must be a key consideration for Government.
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"There needs to be clear evidence that wearing masks, along with other measures, will deliver significant enough benefits to take us out of lockdown to potentially jeopardise NHS mask supply."
The government has faced repeated questioning over the quality and supply of masks and other Personal Protective Equipment (PPE) to frontline medical staff and care workers.
Last week the Health Secretary Matt Hancock said he and his colleagues "won't rest" until all health and care workers have got adequate supplies of kit like masks, gloves and aprons.
The Royal College of Anaesthetists has become the latest medical union to suggest its members should not treat patients without proper equipment.
The Royal College of Nursing had previously told its members that as a last resort they should refuse to treat patieRead More – Source