Gordon Brown said he believed voters were too "sensible" to fall for the BNP.
The Prime Minister hit out at the far-right party as "not British", accusing it of trying to exploit people's concerns on immigration and housing.
In an interview with the BBC Asian Network radio station, Mr Brown was asked about the rise of the BNP in areas such as Barking, east London, where its leader, Nick Griffin, will fight for a Westminster seat.
Mr Brown said: "I think you'll find the British people are far more sensible about the future; I think they see through an ideology based on race."
He added: "I think it's the job of decent people from every party to expose the BNP for what they really are.
"They're trying to exploit people's concerns about immigration and housing, they use them to push their own ideology, which is based on race.
"That ideology of the BNP is totally wrong and it's got to be exposed; it's also not British because our fathers and our grandfathers fought together in a world war to defeat ideology based on race."
North Wales Weekly
