England's white majority is becoming increasingly segregated from growing ethnic populations in urban areas, a new study reveals.
The research, published by Open Democracy, calls on the Government to do more to promote mixed communities, especially in light of the spike in hate crime reported since the Brexit referendum.
The study, conducted by integration experts Professor Ted Cantle and Professor Eric Kaufmann, shows that, while England as a whole is more ethnically mixed, white and minority groups are now more isolated from each other.
The report finds the polarisation is mainly in urban areas. It notes the pace of change is "striking", with some areas seeing a decrease in the white population of more than 50% between 1991 and 2011.
The report says many towns and cities, such as Birmingham, Leicester, Slough, Luton, Bradford and London, have seen areas develop where the white British population is "increasingly dwindling" as minorities increase.
The study finds the "trend towards isolation" is at its greatest in smaller geographic areas, such as wards.
Prof Cantle, who wrote a report into community cohesion in the wake of several race riots in 2001, said: "The antipathy towards some communities may have been much less if we were more integrated and actually lived in mixed areas - all the evidence suggests that prejudice and intolerance is broken down by contact.
"This research shows what is happening on a local level and that is that there is increasing polarisation between the white majority population and minorities across England, particularly in our urban areas. This has gone under the radar, but it is time this became a national priority because cohesion is at stake.
"The focus of policy needs to shift, this is not just about minorities. Politicians and policy-makers need to encourage white British residents to remain in diverse areas; to choose, rather than avoid, diverse areas when they do re-locate, encouraging similar choices with respect to placing pupils in diverse schools; in other words to create a positive choice for mixed areas and a shared society."
Labour's Chuka Umunna, chairman of the All Party Parliamentary Group on Social Integration, said: "During a year in which our country has seemed more divided than at any point in modern history, there are few questions which require investigation more urgently than the matter of how well we are living together.
"Equally, however - at a time in which our political debate has become yet more polarised and media headlines yet more fraught - there are few questions which it can seem harder to get to the bottom of.
"It's clear that, whilst the UK is becoming increasingly diverse, levels of integration are not keeping pace.
"This has real implications for community cohesion - with social segregation having been shown to undermine trust between neighbours, to grow the fear of crime and bolster the prejudice which fuels the politics of recrimination and blame."
The report states: "Where areas have become more mixed, minorities have generally become more isolated from the white British.
"This is a function of the decline of the white British population in those towns and cities in absolute numbers and relative to the increase in minorities in the same areas.
"This results in a growing isolation of the white majority from minorities in urban zones.
"Segregation has been linked to prejudice and intolerance of the 'other' due to the lack of contact and interaction across social and cultural boundaries."
The study comes as the Government is about to deliver a major review into integration, segregation and extremism.