Traders have warned that over-policing the city centre during the bank holiday could put people off visiting the shops.

Sussex Police have said that some nationalist-affiliated groups are planning to meet in Brighton and Hove on Saturday. On the same day, people supporting the UK Uncut movement intend to meet up near the Clock Tower in Brighton. On Monday, a march is planned by the Smash EDO movement.

Andrew Burnyeat, chair of the Brighton Business Improvement District (BID) said he was looking forward to a lively and busy weekend but that the police presence should not put people of visiting and shopping in the area.

He said: “At a meeting with businesses and the police it was suggested that the nationalist groups could be in the high hundreds but I do not think it will be anywhere near that. I think the UK Uncut group are planning a street party rather than a demonstration. So I do not think we need lots of police from other counties on horseback. That will create the wrong atmosphere. It should be a special weekend and nobody should be deterred from coming into the city and enjoying themselves.”

But Roger French, boss at the Brighton and Hove Bus and Coach Company, said he did not know how long services would be disrupted by the UK Uncut event.

He said: “Any disruption at the Clock Tower will immobilise the bus service. It would be unfortunate and disrespectful for innocent people to have their bank holiday spoilt by these groups. Superintendent Steve Whitton said the police will keep business owners notified of developments. He said: “In addition to hundreds of street parties and other local events celebrating the Queen’s Diamond Jubilee, we have been notified of some larger activities taking place.

“Thorough planning for these events is ongoing and we have contacted individuals organising the activities to understand their intentions and anticipated attendees. We have spoken with most of the groups planning to hold events. “It is too early to estimate numbers involved and our planning will ensure we are appropriately resourced. We advise not to over-estimate the number of people likely to take part based on expressions of interest online. Experience shows that the proportion of people who attend such events is usually substantially lower than those joining groups online.

“We are working very closely with our partners in the city to ensure that it is business as usual, making sure any impact on travel companies and local businesses is minimised. We do not anticipate any need for local businesses to close during the events. Similarly, police presence in the city centre will not impact on our response to other incidents or affect participation in smaller Jubilee events.

“We will keep local businesses updated with any significant developments. Throughout the weekend we will also be posting regular updates on our website and through our Sussex Police twitter account – @sussex_ police."