By Finlo Rohrer
BBC News Online
Ken Livingstone and Commission for Racial Equality boss Trevor Phillips have joined MPs and union leaders to launch a united front against the BNP.
The BNP have enjoyed electoral success
They fear the far-right party will enjoy further success at council and European elections this year.
Unite Against Fascism will attempt to organise rallies and campaigns against the BNP across the country.
Activists say a predicted turnout of 18% could lead to the BNP winning a European seat in the North West.
London Mayor Mr Livingstone - just readmitted to the Labour party - said the policies of the government and media hysteria about asylum seekers were fuelling xenophobia.
He told BBC News Online: "The hysteria in the media has led to some people in Britain thinking a quarter of the people in this country are asylum seekers.
Politicians, he went on, "make the mistake of reading too many newspapers... it is bad for your health. I've said to David Blunkett the strategy has been wrong."
Mr Livingstone said the government was guilty of "constantly responding to the agenda set by the Daily Mail that there is this great tide coming".
The mayor said he opposed BNP demonstrations in London because they "disfigure the quality of life" for those in the capital. "We don't allow people to go out and advocate paedophilia," he added.
The party has enjoyed electoral success with 17 councillors, of whom seven were elected in Burnley since it was swept by riots in the summer of 2001.
But BNP national press officer Dr Phill Edwards told BBC News Online the party's opponents wanted to prevent freedom of speech.
He said: "To say we are responsible for racial attacks is rubbish. Wherever we surface there are less racial attacks.
"We are not racists, we are race realists.
"We want to have a debate as to whether or not turning a racially homogenous Britain into a racially multicultural Britain was a good thing."
Dr Edwards said the BNP had nothing to do with fascism.
Addressing the launch of the movement, CRE boss Trevor Phillips said: "In spite of their idleness in office, in spite of their racism, others are still casting ballots for them."
Mr Phillips said the BNP's message was "increasingly voter-friendly", with the party avoiding overt racism and emphasising other aspects of its manifesto as well as its opposition to asylum seekers.
Others speaking at the launch of United Against Fascism included Unison leader Dave Prentis , TUC boss Brendan Barber, MP John Cryer and MEP Glyn Ford.
Anti-Nazi League activist Weyman Bennett said he had been a victim of racist violence in the 1970s and felt the extreme right were weaker in numbers now but stronger in their appeal.
"I've still got the scars from where they attacked me in Stratford, but today the brutes have put on suits and covered up their politics."