The group Unite Against Facism (UAF) has claimed a "victory" over the BNP after both took part in protests in Westminster:
The tweet came after police arrested 58 UAF members during the protests.
Police have confirmed 58 arrests for breach of Section 14 of the Public Order Act from members of the United Against Facism (UAF) protest group near the Houses of Parliament in central London.
The Met Police also said the BNP protest in nearby Old Palace Yard has ended.
Police have confirmed that 31 protesters from the United Against Fascism (UAF) group have been arrested, close to the Houses of Parliament.
Police officers have arrested protesters close to the Houses of Parliament after members of an anti-fascist group refused to move.
The protest of what was believed to be the Unite Against Fascism (UAF) group had been due to take place Whitehall Gardens, at the junction with Whitehall.
But arrests were made after a police liaison officer tried to negotiate with the group - its members had moved to another location behind the Houses of Parliament, where the BNP were protesting.
A Met Police statement read: "From 12.50pm today a group of protesters, believe associated with the UAF counter protest, gathered in Abingdon Street junction with Old Palace Yard. This group reached 300 in total.
"Police attempted to negotiate with the group to move location to the pre arranged penned area in Whitehall."
At around 2.45pm officers began making arrests, while approximately 150 BNP continued to protest in Old Palace Yard, the police said.
BNP leader Nick Griffin warned that the murder of soldier Lee Rigby would not be an isolated incident.
Mr Griffin said: "I believe that by being here today we have at least taken a step to taking the debate to where it needs to be.
"Not about whether the terrible murder of Lee Rigby was isolated, something which will never happen again.
"We're pointing out that it will happen again and again and again until the West disengages with Islam and they leave our country".
When asked about the BNP supporters being significantly outnumbered in Westminster today, Mr Griffin replied: "I think that a number of people who wanted to come have been turned away by the police.
"People have been attacked by the Far Left gang on their way in, so perhaps that has cut numbers".
Police are starting to push back a large group of anti-fascist protesters away from the BNP Assembly Point at Old Palace Yard in central London.
A smaller group of determined protesters remain behind.
The BNP protest has so far attracted a relatively small turnout. A large police presence separates counter-protesters attempting to make their way to the location.
Hundreds of 'anti fascist' protesters have marched from Downing Street to confront BNP protesters gathering outside the Houses of Parliament.
Protest marches in the wake of the murder of soldier Lee Rigby are set to take place today, after his family appealed for calm.
Far-right and opposing groups are planning demonstrations amid increased tensions following the 25-year-old's violent death.
Yesterday his family stressed that the young soldier would not have wanted violent attacks to be carried out in his name, and urged protesters to remain peaceful.
Events have been planned in various locations across the country by the English Defence League, and protest group Unite Against Fascism is due to hold a demonstration in Woolwich at midday.
The British National Party (BNP) will stage a planned march today between Old Palace Yard and the Cenotaph in Whitehall, Westminster.
In a statement issued on the party's website, it said party members are rallying to force the coalition government to act against Islamic hate preachers.
On Thursday, the Metropolitan Police denied the political party permission to march from Woolwich Barracks to the Lewisham Islamic Centre following the death of soldier Lee Rigby.
The authorities said a rally in Woolwich would inflame "current community tensions".