A third of high streets are "degenerating or failing" according to new research published by the Government today.
By 2014 less than 40 per cent of retail spending will be on the high street, according to the study, which also found that over the past decade out of town retail floorspace has increased by almost a third while in towns it has shrunk by 14 per cent.
The findings were revealed alongside a Government-commissioned report aimed at revitalising high streets and shopping centres struggling to attract customers.
TV retail expert Mary Portas proposed a national market day and relaxation of rules to stem shop closures.
She proposed new "town teams" to improve the management of high streets, more affordable car parking and removal of red tape.
"Our high streets are a really important part of pulling people together in a way that a supermarket or shopping mall, however convenient, entertaining and slick, can't."
Prime Minister David Cameron said the Government will review the report and respond next Spring.
Ms Portas said: "Our high streets can be lively, dynamic, exciting and social places that give a sense of belonging and trust to a community. Something which, as the recent riots clearly demonstrated, has been eroded and in some instances eradicated.
"I fundamentally believe that once we invest in and create social capital in the heart of our communities, the economic capital will follow.
"Those who see high streets purely in commercial terms need a reality check, because, without the engagement and collaboration of local people many high streets will die and retailers, landlords and local authorities alike will see their investment wasted.
"This review sets out what I think has led to the decline of our high streets, my vision of the future and the key things I believe we need to put in place to deliver that vision."
She told a press conference that high streets had been "displaced" by out of town shopping centres so people no longer felt they belonged to towns.
She complained that many areas had been "clone towns" and said the recession was giving an opportunity to create something new.
British Retail Consortium director general Stephen Robertson said: "We absolutely agree that high streets make a unique contribution to local neighbourhoods and economies, providing jobs and services and building a sense of community.
"We're delighted that Mary Portas recognises that town centres need to evolve as quickly as customer demands change if they're to remain relevant.
"The report sets out some practical ways to address problems faced by the UK's high streets, many of which go back much further than the economic difficulties of the last few years.
"Prioritising action on business rates and parking is exactly right. These are the key concerns for customers and retailers."
John Walker, chairman of the Federation of Small Businesses, said: "The planning system is hugely important in shaping the character of our high streets and town centres and so our local communities.
"It is vital that the Government and councils take note of these recommendations - in particular, that the provisions in the new National Planning Policy Framework are strong enough to provide the protection needed since there has been a notable shift towards out-of-town retail developments in the last 10 years.
"If no action is taken, the trend is set to continue.
"If we want to ensure vibrant high streets for the future, we need to carefully balance that expansion with ensuring that existing town centres are not unwittingly damaged."
Ms Portas made 28 recommendations which will now be studied in detail by the Department for Communities and Local Government and other Whitehall departments.
She said that among the most important were suggestions that town teams should be established, praising the system in France where senior officials protect town centres.
She also called for the removal of unnecessary regulations to make it easier for people to become market traders, cuts in business rates, and a parking league table so shoppers could see how their town compared on charges.
Ms Portas said the Government had only called in one out of town development since 2008 even though it had been given the chance to review 146 schemes, stressing there should be a new "exceptional sign off" by the Local Government Secretary.
Her report said the way Britons shopped had changed "beyond recognition" - forever, adding: "The phenomenal growth of online retailing, the rise of mobile retailing, the speed and sophistication of the major national and international retailers, the epic experiences offered by today's new breed of shopping mall, combined with a crippling recession, have all conspired to change today's retail landscape."
The only hope high streets have of surviving is to deliver something new, said the report, noting that vacancy rates have doubled over the last two years.
"Although some high streets are thriving, most have a fight on their hands. Many are sickly, others are on the critical list and some are now dead.
Ms Portas said: "We cannot and should not attempt to save every high street but my findings have led me to believe that unless urgent action is taken, the casualties will only continue to multiply."
The report revealed that the number of town centre stores fell by an estimated 25,000 in the past 11 years, with almost one in six shops standing empty.
The internet was identified as one of the main threats to the high street, with retailers needing fewer shops to sell their goods.
Meanwhile shoppers have been "flocking" to out of town developments, which had been allowed to flourish by the UK's planning rules.
Mr Cameron said: "The high street should be at the very heart of every community, bringing people together, providing essential services and creating jobs and investment; so it is vital that we do all what we can to ensure they thrive.
"I am delighted that Mary Portas has produced such a clear vision on how we can create vibrant and diverse town centres and breathe life back into our high street."
Peter Drummond, president of the retail property organisation BCSC, said: "Each town centre needs to find its niche and become a destination that people have a reason to visit. This means full partnership from all stakeholders in a community, including businesses, local authorities and, crucially, customers themselves.
"A strong commitment to town centres in the planning system is vital so that investment is delivered to the heart of communities.
"An aspiration that more schemes not in accordance with local plans - and which may harm a town centre - are effectively 'called in' by the Secretary of State could be part of a solution, but we believe that the heart of the matter lies in proper social, environmental and economic assessments of any project's impact, based on a robust 'town centres first' mechanism."
AA president Edmund King said: "We welcome the attention that this report has given to the importance of parking, in terms of adding vitality to town and city centres. For towns and cities, small and large, adequate free and sensibly-priced parking is the key to economic prosperity.
"Local authorities should not kill the goose that often lays the golden egg - the car-borne shopper who has money to spend. In these tough economic times, local authorities' dash for cash, through ramping up parking income and introducing more restrictions, risks driving people to places where parking is easier."
Adam Marshall, director of policy at the British Chambers of Commerce, said: "If businesses in high streets are able to expand and develop their premises more easily, and attract more customers, then they can help towns and cities flourish, and in turn contribute to the recovery.
"Business rates are a significant barrier for many businesses, and could damage our high streets. The 5.6% increase in rates planned for April is pegged to last September's peak inflation figure, and will be difficult for many retailers, already squeezed by a fall in consumer spending.
"We support Mary Portas's call for councils to use more discretion when applying rates, particularly for start-up companies. If the Government wants to see businesses flourish and create much-needed economic growth, it must go further and reduce the punishing, anti-growth rate rise facing all businesses in 2012."
Peter Box, of the Local Government Association (LGA), said: "Councils have long recognised that our high streets need an urgent revamp, which is why the Local Government Association called for councils to have the power to take over empty shops and use them to provide services such as training centres, libraries or youth clubs, while tenants were found.
"While some of the report's recommendations are positive, such as an increased role for businesses and cracking down on the number of new betting shops, the LGA is extremely concerned that removing regulations around market stalls will result in rogue traders taking advantage of cash-strapped families and flooding the market with dangerous and counterfeit goods.
"Councils play a crucial role in growing local economies and improving high streets, and need to be suitably consulted if they are to achieve this.
"The LGA wants to ensure that any decisions take on board the knowledge of councils, protect their ability to respond to local circumstances, and target the anti-social behaviour, such as littering, metal theft and graffiti which is too often seen on our high streets."
Chris Simpson of shopping comparison website Kelkoo, said: "The Portas Review is positive news for retailers and will hopefully act as a catalyst to rescue our crumbling high streets.
"The report suggests far-reaching and complex solutions so each of them will take time to introduce and could be costly. If they are implemented effectively, it will create a compelling retail environment for shoppers but it will not fix consumers' reluctance to spend in such an uncertain economic climate."
Dirk Vennix, chief executive of the Association of British Bookmakers, said: "The evidence simply does not justify tighter planning regulation for bookmakers. Shop vacancy rates currently stand at over 14% nationally. Betting shops fill a small number of these premises, paying almost £1 billion in tax every year, supporting 100,000 jobs and driving footfall for struggling high streets.
"We are a mainstream leisure industry allowing eight million adults to enjoy their pastime in a safe, fair and regulated environment. It is the consumer who should have the final choice on what can and cannot be enjoyed."
Angus McCarey, UK retail director for eBay, said: "Consumers are driving the changes we're seeing on the high street, which often means they are choosing to mix traditional shopping with browsing online or on their smartphones.
"In addition to the recommendations in support of high street retailers, successful businesses would be advised to be present everywhere consumers want to find them - whether that be on their mobiles, Facebook or shopping sites.
"Making the most of online and mobile shopping can reinvigorate your physical store, for instance by allowing you to clear out of season stock or enable a 'click and collect' service."