The decision by city council to effectively make Richard Dallas a lame duck mayor is one of a number of signs of nationalists' growing anger following the Orange march through Drumcree.
SDLP MP Joe Hendron is tabling a parliamentary question over the alleged presence of a police authority councillor, Trevor Wilson, at a Loyalist blockade in Cookstown in the week of the Drumcree protest. The police authority, after a meeting with the Unionist councillor, says it is taking no further action.
Nationalists are also trying to remove powers from a senior Unionist councillor on Magherafelt district council, following claims that he also took part in a road block.
The Catholic boycott of Protestant businesses in Castlederg, Co Tyrone, was sparked by similar allegations against local Unionist businessmen.
Mr Dallas said he feared other councils would follow the lead of Derry city council and take sanctions against Unionists. The mayor, who was present at a road block on Craigavon Bridge, in the heart of Londonderry, on 10 July, said his council's decision was illegal and that he would be seeking legal advice.
He had been "castigated and demonised" by the nationalist community simply for acting according to his Unionist convictions, he said.
The vote on Wednesday evening means Mr Dallas has been stripped of his mayor's car, official offices and secretarial support; he is not allowed to carry out civic duties, although he insists he will attend some.
Pat Devine, the SDLP leader in Londonderry, said Mr Dallas's actions had gone beyond what was reasonable for a mayor who was supposed to represent the entire local community. He said Mr Dallas would have to make amends before his powers were restored. "The simplest solution would be for him to resign," Mr Devine said.
The week-long protests in early July by Orangemen included setting up hundreds of road blocks around the province and demonstrations against the RUC's decision to ban a march past a Catholic area of Portadown in Co Armagh.
The reversal of the decision in the face of massive Orange protests has caused great anger in the nationalist community, which insists the police gave way to mob rule.
The effect of the disorder surrounding Drumcree has influenced the multi- party peace talks at Stormont, which have adjourned for the summer, and seems likely to be felt in Northern Ireland for a long time.Reuse content