Labour's David Lepper has said that chuggers intimidate shoppers and called for the introduction of a mandatory code of conduct.
Mick Aldridge, chief executive of the Public Fundraising Regulatory Association, said: "We have reduced the amount of activity in Brighton by more than 50 per cent simply because he keeps complaining."
He said the PFRA had tried to contact the Brighton Pavilion MP on many occasions, but he had so far refused to meet. He said Lepper and the local council had problems with face-to-face that did not arise in other places.
Brighton and Hove Council said it would be happy to meet the PFRA.