The government has warned it could make coronavirus vaccine "passports" mandatory for large venues.
On Monday, Boris Johnson confirmed that England’s unlocking of restrictions will go ahead as planned on 19 July.
This will mean almost all legal restrictions on social contact will be removed.
Nightclubs can reopen from next Monday and the entertainment industry has welcomed the decision not to make domestic COVID vaccine passports mandatory at live events.
However, a government document, Moving To Step 4 Of The Roadmap, published on Monday evening, reveals that the NHS COVID Pass, which shows vaccination details or test results, could be made mandatory in future.
Watch: Sajid Javid says unlocking is 'not the end of the road'
The document reads: “The government will work with organisations that operate large, crowded settings where people are likely to be in close proximity to others outside their household to encourage the use of the NHS COVID Pass.
“If sufficient measures are not taken to limit infection, the government will consider mandating the NHS COVID Pass in certain venues at a later date.”
Johnson said on Monday that venues should be cautious.
"As a matter of social responsibility we're urging nightclubs and other venues with large crowds to make use of the NHS Covid Pass, which shows proof of vaccination, a recent negative test or natural immunity as a means of entry,” he said.
But one major nightclub firm has already said it will not be asking its customers for vaccine passports at its doors.
Peter Marks, chief executive of REKOM UK, which owns 42 nightclubs including chains Pryzm, Bar&Beyond, Eden and Fiction, said he was “thrilled” to be able to reopen next Monday “at full capacity and without any requirement for a negative COVID test, something we believe would create a barrier to both customer enjoyment and getting the industry back on its feet”.
Marks added: “We’re able to open in this way because nightclubs in particular are among the best equipped venues in the hospitality sector, and indeed were even prior to the pandemic, for the exact safety measures that are required to reduce the spread of the virus.
“These include air ventilation systems in all our venues which change air every five minutes on average, sanitisation stations throughout all our clubs, increased frequency of cleaning schedules compared to before the pandemic, and highly trained staff and experienced door staff who are well-versed in crowd management protocols.
“Together, these measures mean that clubs are well placed to open and provide unforgettable nights out once again.”
On Monday, health secretary Sajid Javid told the House of Commons that businesses and large events will be encouraged to use the NHS COVID Pass to ask customers for proof they are double-jabbed or have tested negative for coronavirus, but that it would be “non-compulsory”.
Michael Kill, chief executive of the Night Time Industries Association, said the decision to go ahead with the reopening was “the correct one”.
He added: “We look forward to the government providing more guidance for businesses owners – this should be practical and easy to navigate. The government are right not to mandate the use of COVID status certification systems.
“Much of the night-time economy relies on spontaneous consumers and by permitting businesses to opt out the government have allowed for this trade to continue.”
The Music Venue Trust charity said: “For the last 12 months, we have been working tirelessly alongside venue operators to identify ways in which they can reopen every venue safely.
“That work remains at the forefront of everyone’s minds, but today we want to reach out to live music fans and send them a simple message: It’s finally time to revive live.”
Theatres Trust director Jon Morgan said: “This will enable theatres to welcome back full audiences, producing shows that are financially viable and to provide more work for the sector’s precious freelance workforce.
“We know that theatres will do everything in their power to continue to ensure they provide a safe environment for their audiences.”
Last month, a cross-party group of MPs said COVID passports should be scrapped, calling them discriminatory.
Watch: Boris Johnson says 'pandemic is not over' as he confirms 19 July unlocking