BNP leader Nick Griffin banned by Buckingham Palace
BNP leader Nick Griffin has been denied entry to a Buckingham Palace garden party over claims he "overtly" used his invitation for political purposes.
A spokesman said his behaviour had "increased the security threat and the potential discomfort" to other guests.
But Mr Griffin, who had been invited to the event along with all the UK's Euro MPs, told BBC News the ban was an "absolute scandal".
The anti-immigration party's other MEP, Andrew Brons, is attending the party.
Before the ban was imposed Mr Griffin, an MEP for North West England, described the Buckingham Palace invitation on the BNP website as a "highly symbolic breakthrough" for the party and e-mailed supporters asking for questions they would like him to ask the Queen.
Mr Griffin also appeared on GMTV to talk about his invitation to the garden party.
But, in a statement, Buckingham Palace said: "Nick Griffin MEP will be denied entry to today's garden party at Buckingham Palace due to the fact he has overtly used his personal invitation for party political purpose through the media. This in turn has increased the security threat and the potential discomfort to the many other guests also attending.
"Mr Griffin's personal invitation was issued to him as an elected member of the European Parliament.
"The decision to deny entry is not intended to show any disrespect to the democratic process by which the invitation was issued. However, we would apply the same rules to anyone who tried to blatantly politicise their attendance in this way."
Mr Griffin told the BBC he would not try to attend the event.
But he said he believed he had been banned for giving TV interviews about the visit, saying: "It is an absolute scandal. I represent a million voters in the North West. This appears to be a rule invented for me."
In a statement, Mr Griffin said: "Nowhere in the book of rules given to all attendees does it say anything about not giving media interviews and, of course, countless people have done precisely that in the past.
"This decision is an attack on the media and their right to report on important events of the day.
"It is an attack on the right of every person in Britain to get the news of current events reported by the media, and it is an attack on the one million plus patriots who voted for the BNP.
"The move has obviously been made under pressure from the Con-Dem regime who are desperate for any reason to bar the BNP."
As he was leaving BBC studios at Westminster, the BNP leader was confronted by human rights campaigner Peter Tatchell, who accused him of being a "gutless coward".
The BNP leader had been set to attend a Palace garden party last year as a guest of BNP London assembly member Richard Barnbrook but pulled out after an outcry.
In an interview with GMTV on Thursday morning, he said had pulled out of last year's garden party because of "immense pressure" put on the person who had invited him but insisted that this year he had been invited in his own right.
"The Palace have made it very, very clear that they will not discriminate against any elected MEP and I think that's the proper thing to do, so there's no embarrassment there at all," he said.
He said he was "pretty sure" he would not meet the Queen during the party and would not try to speak to her but added: "If we happen to meet over the sandwiches, of course I will."
There are expected to be 8,000 guests at the event which will be hosted by the Queen and also attended by the Duke of Edinburgh.
Other members of the Royal Family who will be mingling on the Palace's lawns include the Duke of York, The Duke and Duchess of Gloucester and the Duke of Kent.
In a separate development, Mr Griffin said the BNP has reached an out-of-court settlement with Unilever, makers of the savoury spread Marmite, but he denied press reports the party had paid the company up to £170,000, saying it was the "tiniest fraction of this amount".
Uniliver threatened legal action after the BNP pictured a jar of Marmite in an online version of a party election broadcast.
Mr Griffin said the spoof had been a response to a Marmite television advertisement, featuring the Hate Marmite Party, which he claimed was an "attack on the BNP".
Unilever confirmed it had settled the case out of court, but said it would not be disclosing the details of the settlement.