Liberal Democrat leader Sir Vince Cable has used the word "nigger" in a speech warning about the rise of identity politics.
Sir Vince was recalling a campaign slogan reportedly used by a Conservative MP in the 1960s, that "if you want a nigger for a neighbour, vote Labour".
The former business secretary was recalling events from 50 years ago, when Enoch Powell gave his famous "rivers of blood" speech and Sir Vince was about to move back to the UK from Kenya.
He said there was panic in Britain at the prospect of immigrants arriving in the UK from Kenya, where Asians who were not Kenyan citizens were no longer welcome.
"There were probably 100,000 people, Hindu, Muslims, Goans and others, who had no future in the country and they started to come to Britain in significant numbers," said Sir Vince.
"This created a panic in Britain and the 100,000 soon became a million in people's imagination, the country was going to be swamped with this vast numbers of people from east Africa.
"And in that environment of panic, racism took hold in quite a serious way. It was already lurking there at the time.
"A few years before, some of you may remember, an important election had been won in Britain by a candidate, a Conservative candidate, and it happened on the platform 'if you want a nigger for a neighbour, vote Labour'. That was the flavour of the time.
"And Mr Enoch Powell, who was a very learned, a very brilliant man, actually, realised that there was an important political vein to be tapped here, and started to make very erudite speeches about race and immigration and identity."
Sir Vince was speaking at a launch event for his party's black and minority ethnic (Bame) candidates at this year's local elections.
During his speech, Sir Vince renewed calls for a change in election rules so parties can field all-Bame shortlists in the selection process for parliamentary candidates.
He also said his party "do not represent the face of Britain in the way that we should and we've got a lot to do to put that right".
Sir Vince told journalists and party activists that Enoch Powell was one of the first British politicians of modern times who understood the power of the politics of identity.
"He wasn't just obsessed by race. He was also passionately anti-European, or passionately pro-Brexit in modern language," Sir Vince said.
"He was passionately concerned about the confessional divide, and indeed he finished his political career as an Ulster Unionist MP.
"So those issues of religion, race, nationality, language, the politics of identity, were what drove him and what has now resurfaced in our present generation."
People in Britain were no longer preoccupied by levels of tax or spending, said Sir Vince, but Scotland, the future of Ireland, Europe and immigration.
"At the time it seemed utterly preposterous that Britain could be a country like that, preoccupied by those subjects, but it is, and we know it is," he added.
"The politics of identity is what is now driving and dominating our society."