Andrew Lloyd Webber has backed down over his threat to reopen his theatres without social distancing after being warned his entire staff and the audience could have been fined hundreds of pounds each.

In a broad swipe at the Government’s dithering over the lifting of Covid-19 restrictions, Lord Lloyd-Webber also said on Thursday he was declining an offer made to him by Boris Johnson to take part in a pilot scheme that would have allowed opening at full capacity.

Snubbing the Prime Minister’s offer, the composer and impresario said it was unfair to be singled out for special treatment by Downing Street.

Lord Lloyd-Webber’s new musical Cinderella will now begin previews on 25 June “at the Government’s arbitrary 50 per cent capacity” with disappointed theatre-goers given either refunds or a new date to see the show. Lord Lloyd-Webber said he would "personally bear the losses" while it remains economically unviable.

The 73-year-old had caused Mr Johnson deep embarrassment when he threatened to break the law and open fully  after it emerged that the Prime Minister had decided he could no longer stick to his roadmap on lifting restrictions.

On Thursday, Public Health England issued new figures showing a 79 per cent rise in one week in cases of the Delta or Indian variant – from 42,323 cases to 75,953. The most recent data shows 99 per cent of coronavirus cases in the UK are now from the new, more virulent strain. 

There were 10,476 new cases confirmed on Thursday and 11 deaths.

In his statement Lord Lloyd-Webber said: “After a long week of Government delay and confusion, I confirm that I cannot and will not take part in yet another pilot scheme around the reopening of theatres, as suggested by the Prime Minister on Monday. 

“I have made it crystal clear that I would only be able to participate if others were involved and the rest of the industry – theatre and music – were treated equally. This has not been confirmed to me.”

Lord Lloyd-Webber, a former Conservative peer who quit the House of Lords in 2017, said the theatre industry was being treated as an "afterthought and undervalued" by the Government – and contrasted its treatment with Wimbledon which began selling tickets on Thursday. 

He went on: "Cinderella will perform its first preview next Friday 25th June. Like theatres and venues across the country, this will sadly be at the Government’s arbitrary 50 per cent capacity, not the 100 per cent we so passionately wanted. 

"Having taken legal opinion from senior counsel, if we had gone ahead at 100 per cent it would be very likely that every member of my cast, crew and orchestra, the front and backstage staff, plus our loyal audience members, could be individually fined hundreds of pounds, which I couldn’t possibly risk. 

"If it were just me, I would happily risk arrest and fines to make a stand and lead the live music and theatre industry back to the full capacities we so desperately need."

He said he "could not look my young cast and crew in the eyes to tell them we were delaying or closing down", adding: "So, I have made the decision to personally bear the losses until we fully open on – or hopefully before – 19 July."

He apologised to ticket holders who now face re-organising their theatre dates , but insisted: "Rest assured, come hell or high water, we will get you to the ball.” 

In a cheerier note, Lord Lloyd-Webber also thanked the public for messages of support after he had told The Telegraph last week that he was prepared to go to prison in defiance of Covid-19 laws. "Finally, can I thank the thousands of people who have contacted me with messages of support," he said. "Including those who wanted to come and bring me cake in jail."

A Government source hit back at Lord Lloyd-Webber, and told The Telegraph:  “We’ve given him the opportunity to operate at 100 per cent capacity through the Government’s pilot programme, which is exactly what he wanted.

“It’s completely baffling that he’s pulled out of this. We have no idea why he’s done it. It’s completely bemusing to all of us.”

Mr Johnson said on Thursday he believed restrictions on social distancing would be lifted on 19 July, the new date for his revised roadmap. "I think that’s certainly what the data continues to indicate," he said on a visit to a college in West Yorkshire.

More than 800 people are now in hospital with the Delta strain – up more than 50 per cent on the previous week. Up to 17 June, 35,507,916 people had been given first doses of a vaccine – equivalent to 80.2 per cent of the adult population.