Like the television in a bar that you can’t keep your eyes off, a network of giant outdoor screens is about to provide a constant neon distraction from the charms of Britain’s historic market squares during the 2012 Olympics.

Organisers keen to ensure that the public do not miss a moment of the world’s biggest sporting event are planning to broadcast around the clock in 60 towns and cities.

The scheme to operate the largest network of public screens seen in Britain, announced today in partnership with the BBC, has been condemned as irresponsible by heritage groups.

The Commission for Architecture and the Built Environment (CABE) accused the London Olympics organisers of plastering the country in “digital wallpaper” after it emerged that many of the 400-inch screens would not be temporary, as originally suggested.

The first batch of screens will broadcast live coverage of the Beijing Olympics from August 8 and will become the focus of a national party on August 24 when the closing ceremony of the Games marks the official hand-over to London.

They will be Bluetooth-enabled, allowing members of the public to upload and download images and even play computer games. On hand-over day, which falls on a Bank Holiday weekend, regional choirs will assemble at the “live sites” to lead a 15-minute mass singalong incorporating a national song designed to warm up the public for 2012.

The idea of temporary screens took off at the Sydney Games in 2000 and proved popular during the 2006 football World Cup in which the Germans set up “fan zones” in 12 cities. Olympics organisers have so far announced eight permanent sites – in Bristol, Cardiff, Middlesbrough, Norwich, Plymouth, Portsmouth, Swansea and Walthamstow – and 22 temporary ones. They require full planning permission.

Civic experts, who recently heard a presentation by London 2012 after raising concerns about long-term planning issues, told The Times that the real ambition was for between 45 and 60 permanent screens. They claimed that Olympics organisers were being deliberately secretive about the true scale of the project.

“It’s not that we don’t believe in fun in public spaces but this is not urban regeneration. It’s an outdoor Currys and I find it worrying if not irresponsible,” Sarah Gaventa, director of CABE Space, said. “Without funding or proper curating, we’re going to end up with News 24 and EastEnders.”

The CABE wrote to Tessa Jowell, the Olympics Minister, last month after being “fobbed off” by 2012 executives running the cultural programme.

Other agencies said that the screens, which will have a ten-year lifespan, would destroy the aesthetics of towns with historical significance. Issues of noise pollution, crowd control and public drinking had not been considered, they added.

“This is potentially disastrous,” Michael Loveday, chairman of Living Streets, a charity for improved public spaces, said. “These things are huge – putting one randomly in a small market town will have a dramatic impact. What’s to stop it turning into something awful like a 24-hour pop video?"

The screens, which are muted overnight but emit a constant neon flicker, have been piloted by the BBC in Hull, Leeds, Bradford, Rotherham, Liverpool, Manchester, Derby and Birmingham.

The London Olympic Organising Committee is supplying the screens but local authorities will be responsible for maintenance costs. The BBC will provide the content. The project received £2.6 million of National Lottery funds but the total cost is believed to be £45 million, covered by sponsorship from BT and Lloyds TSB.

English Heritage, the Government’s adviser on historic properties, thinks that this money could be better spent. Philip Davies, its planning director, said: “It’s hard to see how the screens will add to the characters of historic city centres. The one in Hull is a horror on stalks and totally dominates the city centre.”

Civic rights groups share the concern. “This is a monstrous proposal,” Simon Davies, director of Privacy International, said. “There has to be a limit on the Orwellian intrusion into our serenity.” The Olympic organising committee said that talks with the CABE were continuing, adding: “We share the ambition that the local authorities take the best advice to make sure the screens work for all.”