The President of the Chamber of Commerce in Derry is urging flag protestors not to jeapordise business in the city.
Philip Gilliland says the chamber is careful to remain politically independent.
However, he says it is estimated that the protests in Belfast will have cost retailers in that city £20m in lost trade, which will be a blow that many of them will not recover from. Traders in Derry, he says, simply could not sustain that sort of impact if shoppers felt uncomfortable with coming into town because of protests.
Mr Gililand says it's vital that shoppers support their local businesses, that protesters to do nothing to prevent that trade from taking place.