Chancellor Gordon Brown said race laws may have to be changed after British National Party leader Nick Griffin was cleared by a jury of stirring up racial hatred.
The far-right politician sprayed Champagne and declared a victory against the Government and the political establishment after the all-white jury found him not guilty.
But Mr Brown said most people would find some of Mr Griffin’s words offensive and pledged a legislative rethink if it was required to stamp out racial hatred.
"Any preaching of religious or racial hatred will offend mainstream opinion in this country and I think we have got to do whatever we can to root it out, from whatever quarter it comes," he told the BBC.
"If that means that we have to look at the laws again, I think we will have to do so."
Mr Griffin, a 47-year-old Cambridge graduate, was greeted by jubilant supporters outside court after the jury took five hours to clear him and BNP activist Mark Collett of stirring up racial hatred in a series of speeches in Keighley, West Yorkshire, in 2004.
The speeches were filmed by a BBC undercover reporter at BNP meetings in pubs in the town.
Earlier this year, Mr Griffin and Mr Collett, 26, were cleared of a series of similar charges but a jury failed to reach verdicts on others.
Crown Prosecution Service lawyer Helen Allen defended the decision to bring charges, taken with the approval of the Attorney General on the basis of a "realistic prospect of conviction".
Mr Griffin told cheering supporters: "We have shown Tony Blair, the Government and the BBC, they can take our taxes but they cannot take our hearts, they cannot take our tongues and they cannot take our freedom."
He battled to be heard against a barrage of abuse from a small band of anti-fascist demonstrators who were held back behind police pens about 20 yards from Mr Griffin and Mr Collett.
He said the Government had spent almost #1 million attempting to jail him and Mr Collett over the course of the two trials.
Mr Collett said the BBC had "abused their position"
The week-long trial heard how speeches by Mr Griffin and Mr Collett were filmed for the BBC documentary Secret Agent by a reporter who posed for months as BNP member.
Former BNP leader John Tyndall was also charged after featuring in the film but he died before the case came to trial.
In the speeches Mr Griffin discussed at length his beliefs about multi-cultural Britain, describing Islam as a "wicked, vicious faith" and saying Muslims were turning Britain into a "multi-racial hell hole".
Summing up the case yesterday, the Recorder of Leeds, Judge Norman Jones QC, said freedom of speech extended to "unpopular" views and "those which many people may find unacceptable, unpalatable and sensitive", he added.
"Along with those rights come rights and duties not to abuse them."
Griffin told the jury his speech was not an attack on Asians in general, but on Muslims.
Mr Griffin, of Llanerfyl, Powys, Mid Wales, was cleared of one count of using words or behaviour intended to stir up racial hatred and an alternative count of using words or behaviour likely to stir up racial hatred.
Mr Collett, of Swithland Lane, Rothley, Leicestershire, was cleared of two charges of using words or behaviour intended to stir up racial hatred and two alternative counts of using words or behaviour likely to stir up racial hatred.
In February, Mr Griffin walked free from court after he was cleared of two similar race hate charges relating to a speech he made at Morley Town Hall, near Leeds.
The jury at Leeds Crown Court in February failed to reach verdicts on two further allegations he faced and the retrial, which ended yesterday, was ordered over the speech he made in Keighley.
During the same earlier trial, Collett was cleared of charges in relation to two speeches, and the jury failed to reach verdicts on two others. West Yorkshire Police said yesterday's verdict was "a matter for the court" while campaign group Unite Against Fascism described it as "a travesty of justice".