A request for fans not to bring the national flag to a major rock concert in Australia has provoked outrage.
Organisers say the flag was abused in 2005 race riots
Organisers of the Big Day Out said they feared a repeat of "racism disguised as patriotism" at last year's event, which came weeks after race riots in Sydney.
Politicians and veteran groups have strongly condemned the move.
PM John Howard said the "proposition" that the display of the flag should ever be banned "is offensive and it will be to millions of Australians".
The Big Day Out is Australia's biggest outdoor rock concert, held in Sydney and other major cities around the country.
It often features some of the world's most well-known bands, and tickets for this year's concert sold out in a matter of hours.
In a statement on the Big Day Out website, organisers said, in recent times, there had been an "increased incidence of flags brandished aggressively and this has led to increased tension.
"With all this in mind and the aim to create a happy, peaceful, musical event, organisers would like to request that fans please leave their flags at home."
The concert has already been brought forward 24 hours, to take place on Thursday, the eve of Australia's national day, to avoid any nationalistic overtones.
Event producer Ken West said he was concerned by the use of the flag by white mobs during race riots on Sydney's Cronulla Beach in December 2005, and by some fans at the Big Day Out concert a month later.
"The Australian flag was being used as gang colours," he was quoted by The Daily Telegraph newspaper as saying. "It was racism disguised as patriotism and I'm not going to tolerate it."
He also said he was disturbed by clashes at last week's Australian Open tennis tournament in Melbourne between ethnic Croatian and Serbian fans.
The saga has prompted protests across the political spectrum - and especially from Australian war veterans, who say the flag is a symbol of national unity rather than division.
Don Rowe, president of a veterans group in New South Wales state, said the event organisers were trying to bar a symbol which had served through two world wars.
Prime Minister John Howard added: "The event organisers should not ram their peculiar political views down the throats of young Australians who are only interested in a good day out."