Dr Anthony S. Fauci, the US’s top infectious disease expert, said on Friday that the country should consider implementing a first-ever national mandate requiring masks, to help control a surge in coronavirus cases across the US that has become the most severe to date.

Appearing on CNN, Dr Fauci said that enforcing such a mandate would be difficult. But with conditions worsening across disparate regions of the country, he said he could be inclined to recommend the dramatic measure.

“There’s going to be a difficulty enforcing it,” he said, “but if everyone agrees that this is something that’s important and they mandate it and everybody pulls together and say, you know, we’re going to mandate it but let’s just do it, I think that would be a great idea to have everybody do it uniformly.” Most states have imposed mask requirements to varying degrees.