An ex-BNP councillor in Burnley says she is backing an anti-fascist group at the next local and European elections.
Councillor Stowe said she was disillusioned with the BNP
But Maureen Stowe has refused to explain in detail the reasons for her apparent political U-turn.
She said "the time was right" to leave the BNP and would probably support the Unite Against Fascism anti-BNP campaign at the May elections.
The group will not field candidates, but aims to raise awareness and urge people not to vote BNP.
Mrs Stowe said she joined the BNP because she thought it would do good for the town and had become disillusioned with the Labour council.
But she said she had become equally disillusioned with the BNP shortly after being elected and her only regret was not leaving sooner.
She said she did not know the details of the BNP's policies when she was elected in May 2003.
She told BBC News Online: "At the time, they said they could change things in the town, everyone had got upset with Labour.
"They were going to deal with anti-social behaviour and that sort of thing."
When told that the BNP backed the voluntary resettlement of non-whites to "their lands of ethnic origin", the councillor for Brunshaw ward said: "I hadn't heard that."
She said: "I have always said I am not a racist. I believe that the council has worked hard for this town and it would be a shame for the BNP to step in and spoil it all."
She added she believed those who had voted for her would not be upset with her, saying: "I think people voted for me because they knew me - the people in the ward.
"I am still there for them as their councillor, I haven't changed for them."
She added: "I don't regret joining. What I do regret is taking so long to realise."
Threat to democracy
But she refused to explain which of the party's policies she had become dissatisfied with.
Ron Spencer, from Burnley Trades Council, which supports the Unite Against Fascism campaign, said: "I'm very pleased that Councillor Stowe has seen through the lies and the deceit and the hatred that the BNP and other fascist organisations try to breed.
"I hope that there will be many more who see through this and will come to join us to unite against this threat to democracy and peace and people's very liberty, in fact."
The BNP has denied it is a fascist party and has claimed opposition parties are trying to prevent freedom of speech.
The leader of the BNP party in Burnley, Councillor Leonard Starr, said: "I doubt she can even spell fascism, let alone understand what it means.
"I've nothing but disgust for her. She has turned so many times it's unbelievable.
"I can't believe that someone can go through so many changes in the space of a few weeks."