David Blunkett's call on immigrants to adopt "British norms of acceptability" has triggered a row over racism and multicultural policy.

The home secretary's call for ethnic minorities to develop a new sense of Britishness comes as three reports to be published tomorrow identify racial segregation and isolation in Burnley, Oldham and Bradford as key factors in riots last summer.

"We will not tolerate what we would not accept ourselves under the guise of accepting a different cultural difference," he told The Independent on Sunday. "We have norms of acceptability and those who come into our home - for that is what it is - should accept those norms just as we would have to do if we went elsewhere."

Blunkett denies that he is demanding that immigrants assimilate, calling for a "two-way street". "If we are going to have social cohesion we have got to develop a sense of identity and a sense of belonging," he said.

The row has raised concerns that the home secretary's comments could offer ammunition to racists and are a diversion form the root causes of racism.

The reports will confirm that the British National Party was involved in the summer's disturbances but will also highlight weak local leadership and the self-imposed segregation of ethnic minority groups.