Mr Griffin hopes to become the British National Party's first MEP.
British National Party (BNP) chairman Nick Griffin has defended a party leaflet which says that black Britons and Asian Britons "do not exist".
The BNP's "Language and Concepts Discipline Manual" says the term used should be "racial foreigners".
In a BBC interview, Mr Griffin said to call such people British was a sort of "bloodless genocide" because it denied indigenous people their own identity.
Mr Griffin is standing in the European Parliament elections in June.
'Politically correct fiction'
The BNP manual, leaked to the anti-fascist group Searchlight and seen by the BBC, says that "BNP activists and writers should never refer to 'black Britons' or 'Asian Britons' etc, for the simple reason that such persons do not exist".
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Thursday 23 April, 2009, BBC Radio 4 at 2000 BST
"These people are 'black residents' of the UK etc, and are no more British than an Englishman living in Hong Kong is Chinese.
"Collectively, foreign residents of other races should be referred to as 'racial foreigners', a non-pejorative term... The key in such matters is above all to maintain necessary distinctions while avoiding provocation and insult."
The manual describes the BNP's "ultimate aim" as the "lawful, humane and voluntary repatriation of the resident foreigners of the UK".
Commenting on the leaflet's content, Mr Griffin told The Report on Radio 4 that although "in civic terms they are British, British also has a meaning as an ethnic description".
"We don't subscribe to the politically correct fiction that just because they happen to be born in Britain, a Pakistani is a Briton. They're not; they remain of Pakistani stock.
"You can't say that especially large numbers of people can come from the rest of the world and assume an English identity without denying the English their own identity, and I would say that's wrong," he added.
"In a very subtle way, it's a sort of bloodless genocide."
Mr Griffin was also candid about the significance the BNP places on the slogan "British jobs for British workers".
I certainly regret the fact that the BNP could be using language we've used in order to legitimise what I regard as divisive, pernicious policies
Hazel Blears, Communities Minister
The Prime Minister Gordon Brown famously used the phrase in a speech about skills training.
Mr Griffin claimed the prime minister borrowed the rhetoric from his party.
"When I heard Gordon Brown use our slogan - British jobs for British workers - I was delighted," he said.
"What Mr Brown actually meant when he said British jobs for British workers is of course down to Mr Brown.
"But there's no doubt that it was perceived - and was intended to be perceived - by millions of ordinary Brits as meaning that they would be at the front of the queue in front of economic migrants from anywhere else in the world."
"So having raised our slogan, promised it, we feel that he's legitimised our message."
Hazel Blears, secretary of state for Communities and Local Government, said she rejected Mr Griffin's charge that the prime minister's use of the phrase represents an endorsement of BNP policy.
"I certainly regret the fact that the BNP could be using language we've used in order to legitimise what I regard as divisive, pernicious policies which will actually do working class people no good at all," she said.
"What I don't regret is the fact that we need to have a proper discussion in this country about making sure that British people have a chance to get the skills, the education, to be able to get the jobs of the future."
The "British jobs for British workers" slogan was widely repeated during the BNP's recent council by-election campaign in Moston in Manchester, where the party's candidate, local publican Derek Adams, came second.
Moston is in the North West region, where the BNP hopes its supporters will elect Mr Griffin as the party's first MEP in the European Parliamentary elections on 4 June. Nominations close on 7 May.
Under the proportional representation system used in European elections, the BNP would need around 9% of the vote; in the last elections the party won 6.4%.
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