Alan Milburn
Alan Milburn says a new geography of disadvantage in England has been discoveredReuters

England faces the threat of a "local lottery" in social mobility as London and the capital's commuter belt pulls away from the rest of country in prospects for young people. The Social Mobility Commission issued the warning after releasing its first index into the subject.

The research revealed that almost half (46%) of the country's social mobility hotspots were in London, whereas coastal areas and industrial towns are becoming "cold spots". Places like Doncaster, Mansfield, Stoke, Blackpool and Great Yarmouth are performing badly on both educational measures and adulthood outcomes, the study found.

Alan Milburn, the chairperson of the Social Mobility Commission, said: "The social mobility index uncovers a new geography of disadvantage in England. It lays bare the local lottery in social mobility.

"It gets beneath the surface of a crude north-south divide and calls into question some of the conventional wisdom about where disadvantage is now located. It is shocking that many of the richest areas of the country are the ones failing their poorest children the most.

He added: "This report is a wake-up call for educators and employers as well as policy-makers, both local and national. If social mobility is to take off, much more will need to be done if there is to be a level playing field of opportunity in our country. The gulf between the ambition of a one nation Britain and today's reality of a divided Britain is far too wide."

The research also revealed that England's major cities are failing to "be the places of opportunity they should be". While London is way ahead no other major cities do well.

The study also found that many of the richest places in England are doing worse than places that are much poorer. "While there is undoubtedly a link between the affluence of a local area and the life chances of disadvantaged young people – with richer areas tending to do better against the social mobility index than poorer areas – there are many affluent areas that fail young people from poor backgrounds", the report said.

A Department for Education spokesman said: "All of our reforms are underpinned by a total commitment to fairness and social justice. That is why raising standards for every child, regardless of circumstances, is part of our plan to ensure everyone can achieve their full potential.

"Thanks to our reforms there are now 1.4million more pupils being taught in 'good' or 'outstanding' schools compared to 2010. And over this Parliament we are determined to spread this educational excellence everywhere, extending true social mobility for all."

The Cabinet Office had not responded to a request for comment at the time of publication.