Anti-capitalism protesters are planning a major demonstration on the first day of this year's Labour Party conference in Brighton.
Organisers claim they expect 10,000 demonstrators and say they have not ruled out "direct action" on the day.
A similar protest at last year's Labour conference in Brighton attracted between 500 and 1,000 protesters and there were no clashes with police.
Sussex Police are aware of the latest plans but would not be drawn on whether they have made contingency plans.
A force spokesman said: "Sussex Police recognise the Labour Party conference is an opportunity for groups to demonstrate.
"Our primary focus is security and public safety. We seek to work closely with the organisers of any group to facilitate lawful and peaceful protests."
Guy Taylor, of Globalise Resistance, one of the groups planning the demonstration on September 30, said he did not expect violent protests but he would not rule out direct action against conference sites.
He said: "I think we will get at least 10,000 people and I figure it will have a big impact.
"I don't think there is any danger of violent protest. There is always a possibility of direct action. It depends on other things, like the reaction of Her Majesty's police."
Globalise Resistance took protesters to the G8 meetings in Genoa last month, where one demonstrator was shot dead.
Mr Taylor said the aim was not to disrupt the Labour conference but to give ordinary people the chance to make their voices heard.
He said: "I think the conference is a complete and utter sham. They have admitted they ignore anything anyone says."
August 15, 2001
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