Will Paterson's voice echoes around a large dark room at the E1 nightclub, once one of London's biggest party venues but which has not seen a customer for 16 months.

The venue, on an industrial estate in the east of the British capital, opened to a fanfare in 2017 with a marathon 27-hour rave and regularly played host to 1,600 clubbers.

But after months of preparations to finally reopen on June 21, club manager Paterson is struggling to put a gloss on Boris Johnson's latest announcement of a four-week delay in lifting all coronavirus restrictions.

The prime minister's move on Monday was designed to stem the spread of the Delta variant of the virus after a surge in cases of the highly infectious strain first identified in India.

UK nightclubs, like the PRYZM in Leeds, have been gearing up for the June 21 reopening, only to have plans put on ice UK nightclubs, like the PRYZM in Leeds, have been gearing up for the June 21 reopening, only to have plans put on ice Photo: AFP / OLI SCARFF

Restrictions have been gradually eased since March and as part of the government's roadmap out of lockdown, nightclubs were always going to be the last to reopen.

But Paterson said having to stay shut even longer is frustrating.

"There were many, many steps we've had to take over the last few months to make sure we'd be able to open," he told AFP.

People have gradually become more confident about socialising indoors because of high vaccination rates.

Some staff have already left the sector, exacerbating losses of workers who are EU nationals because of new employment rules after Brexit. Some staff have already left the sector, exacerbating losses of workers who are EU nationals because of new employment rules after Brexit. Photo: AFP / OLI SCARFF

In practical terms, venues have ordered in supplies of food and drinks.

Now that is on hold, and could force even more people in the industry to seek work elsewhere, he said.

"They're going to be thinking to themselves, 'how many times will reopening have to be delayed before I think that it's not an industry that's stable enough to support my food, my rent, my living costs?'" he added.

Restrictions have been gradually eased since March as part of the government's roadmap out of lockdown Restrictions have been gradually eased since March as part of the government's roadmap out of lockdown Photo: AFP / Niklas HALLE'N

Like many places in the beleaguered hospitality and entertainment sector, E1 has had to diversify to survive, by opening an outdoor pub.

But some staff have already left the sector, exacerbating losses of workers who are EU nationals because of new employment rules after Brexit.

Johnson's postponement of so-called "Freedom Day" has caused outrage even among some of his own Conservative MPs, given the success of the vaccination programme.

Boris Johnson has insisted the extension of restrictions would be the last Boris Johnson has insisted the extension of restrictions would be the last Photo: POOL / Matt Dunham

Latest figures show that about 80 percent of the adult population has had a first dose of a Covid-19 vaccine, and about 57 percent both doses.

"Many in the industry saw the positive message some two weeks ago from the prime minister and started to ramp up their preparation," said Michael Kill, chief executive of the Night Time Industries Association, a trade body.

"They got to the point where they committed financially to be able to open on June 21."

"Each week of the delay will cost pubs ?100 million ($140 million, 116 million euros)," said the head of the British Beer & Pub Association, Emma McClarkin.

The association has been one of the most vocal critics of coronavirus closures and says the latest move "increases the chances of pubs disappearing forever".

For Kill, nightclubs run a similar risk and estimated that a quarter of venues could close in the next month, as government support for hard-hit businesses is phased out.

Despite criticism from business, the British public, which has seen almost 128,000 deaths from Covid-19 since last year, appears convinced of the need for a delay.

Some 71 percent of respondents overall backed the move, against 24 percent who did not, according to a YouGov poll published on Monday.

Even among those aged 18-24, the support held firm, although the gap narrowed to 54 percent in favour and 34 percent against.

"Business understands the need to move cautiously," said Kate Nicholls, chief executive of UKHospitality, which represents businesses including bars, hotels, bowling alleys and theme parks.

"But this (the delay) is a perfect storm of suppressed revenue and increased costs that can be eased by extending rate relief and rent protection."

Johnson insisted the extension of restrictions would be the last. Industry professionals are not convinced -- and support is growing for a full lifting in four weeks' time.

In a Savanta ComRes poll published on Tuesday, 43 percent of respondents said all social distancing measures should be scrapped after July 19. More than half said they were worried the restrictions could go on indefinitely.

"Youngsters are getting frustrated, they are socially starved," said Kill. "We need the government to stick to the plan."