Modern Britain is still suffering from "deep divides" in society, with a wide gulf between the life chances of the rich and poor, a major report has warned.
There is a growing split by income and by class, with privately-educated pupils still dominating the top professions and top earners increasing their wealth while more than a million youngsters live in poverty.
While some progress has been made on child poverty, raising employment levels and boosting the academic results of disadvantaged youngsters, this has been limited and remains too slow, according to the Social Mobility and Poverty Commission.
In its third annual State of the Nation report, the Commission argues that Britain "does not provide a level playing field on which people can aspire to succeed".
While it praises David Cameron and his "One Nation" commitment to cut poverty and improve life chances for all, the hard-hitting report concludes that there is a wide gap between this aim and current reality, and that the present response is not enough
"The divisions in our nation run deep and, arguably, they are deepening," the Commission says.
It suggests that there is no longer just a North/South divide in opportunity and wealth, but that "fissures" have opened up within England.
"It is only 100 miles from Norwich to St Albans, but they are like two different countries," the report says.
On average, men live three years longer and women nearly two years longer in St Albans than in Norwich.
The average salary is around £13,000 higher in the former and there are nearly twice as many professional jobs.
Unemployment in Norwich is almost double that of St Albans, children are over three times as likely to be in low-income families and much less likely to gain five good GCSEs.
The report argues that there is a "growing social divide by income and by class" across Britain.
While the income share of the top 10% has increased from 28% to 39% since 1979 and the income share of the top one percent has gone from six percent to 13%, at the other end of society, there are over a million children living in persistent poverty, who do not have access to many of the opportunities available in modern society, it says.
The Commission, led by former Labour minister Alan Milburn, also takes aim at the exclusivity of many top professions, saying "those who rise to the top in Britain today look remarkably similar to those who rose to the top half a century ago".
Around 71% of senior judges, 62% of senior armed forces officers and 55% of civil service department heads attended private schools, which collectively educate around seven per cent of the population.
"Of course, the best people need to be in the top jobs - and there are many good people that come from private schools and go to top universities.
"But there can be few people who believe that the sum total of talent resides in just seven per cent of pupils in the country's schools."
The Commission concludes: "It seems that Britain may have reached an inflection point.
"If the trends of recent decades continue we will become a society that is ever more divided.
"If, on the other hand the One Nation aspiration can be translated into real action, Britain could become the most open, fair and mobile society in the modern world."
It adds: "Our conclusion is that, despite many welcome initiatives, the current policy response - by educators and employers as much as governments - falls well short of the political ambition."
The report sets out a series of recommendations to boost social mobility, covering areas from early years and schools to apprenticeships, universities and employment.