Theatres will only be able to open again when social distancing is scrapped entirely, according to the chief executive of Theatre Royal Plymouth.
Adrian Vinken warned that over 100 jobs at the theatre – a third of its operation – could be at risk unless doors open again soon.
However, while the government will allow theatres to reopen from 4 July, this does not include for live performances – a change Vinken said was unlikely to benefit theatres, such as his, that do not have large screens to compete with cinemas.
Asked on BBC Radio 4's Today programme whether the new measure would have any benefit for his organisation, Vinken said: "None whatsoever.
"Only when social distancing is a thing of the past and people feel comfortable and able to return safely to the theatre – the sheer economics of large-scale theatre just won't work.”
His comments came as one of Britain’s leading playwrights warned that the UK's cultural landscape is "in collapse" as the future of theatres hangs in the balance.
James Graham, who wrote Ink, This House and The Vote, as well as TV dramas Quiz and Brexit: The Uncivil War, expressed dismay at the situation and highlighted the plight of Theatre Royal Plymouth.
He wrote on Twitter: "That's one of the largest, most well attended theatres outside London. A theatre that now has no artists, and they won't be coming back. Our world-beating cultural landscape is in collapse.”
The prime minister said on Tuesday that social distancing rules would be cut from two metres to "one metre plus" but the date when shows can resume in theatres is still to be determined.
He said the government will "work with the arts industry" towards their reopening.
Philippa Childs, head of the Broadcasting, Entertainment, Communications and Theatre Union, said: “Even with reduced social distancing there are also questions about whether independent cinemas and art galleries will be financially viable.
"Workers in the theatre industry and live events will be astonished that the government is still discussing plans to work with experts when the issues have been clear for some time now and the industry is desperate for help now.”
She added: "Reducing social distancing from two metres to one metre will have little effect on the challenges facing theatres. Theatres are a crucial part of cultural life and the economy in this country.
"A comprehensive rescue and recovery package is needed and the government has failed, once again, to recognise the seriousness of the situation."
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