White Britons are now a minority group in three towns and cities outside of London, a study has found, but says the numbers of people who identify as British nationals remains high.
A report by the University of Manchester, based on the 2011 census, cites the influx of three million immigrants over the last decade for the demographic sea-change in Leicester, Luton and Slough.
Professor Ludi Simpson, who led the study said: “In Slough, Luton and Leicester, the white British group remains the largest by far - though for the first time they do not account for the majority of the population as a whole.
"These and all other towns and cities in England and Wales are already diverse with many different ethnic minorities."
In Luton, where 45% of people are white British, 81% of people identify as British. Nationally, the figure is 97%.
Across the country and excluding single person residences, 1 in 8 households contains more than one ethnic group.
In addition, the number of people identifying themselves as "mixed ethnicity" has risen 50% in 10 years.
Simpson added: “These findings should now put to bed the arguments of those people in politics and the media who say the British identity is somehow under threat by a segregated society.”
Labour leader, Ed Miliband, said last month that too little was being done to tackle the "realities of segregation" in "multi-ethnic, diverse Britain".
He said: "People of mixed race are among the fastest-growing group in the population of our country.
"We are stronger for it - and I love Britain for it. It gives us access to new ideas, new perspectives, new energies.
"But at the same time we know there is anxiety about immigration and what it means for our culture. The answer is not to sweep it under the carpet."
The position is not a new one. Back in 2005, former chair of the Equality and Human Rights Commission, Trevor Phillips, said: "People share space in Britain's towns and cities but do not know who each other are."
The findings come just a day after a report, sponsored by the Government's Economic and Social Research Council, that declared that one in five Britons will be from an ethnic minority by 2050.
Simpson said: “This research has an important context: local government deals with ethnic and cultural diversity everyday in rural and urban neighbourhoods and those with powerful organisations to represent them and those without.
“So we need to understand changing ethnic composition to understand our citizens’ changing needs.
“Housing, school meals, care of older people, cultural and entertainment facilities, funeral services and many other aspects of local services are all intrinsically affected.”
The white British population is lowest in the London borough of Newham where they make up only 17% of the population.
Across the capital, 3.7m people (44.9%) identify as white British, down from 4.3m at the time of the last census in 2001.