The Ulster Unionist Party leader, Mr David Trimble, has described Derry City Council's decision to change the name of the city officially from Londonderry to Derry as "an exercise in crude sectarian triumphalism".
During a visit to the city yesterday, Mr Trimble said the controversial decision taken by the council last Tuesday could impact on his party's relationships with the SDLP and Sinn Féin, adding that it flew in the face of the Good Friday agreement.
"I can remember over the last 30 to 40 years many nationalists from this city talking to us about the crudeness of majoritarianism and of the need to recognise various traditions.
"That, of course, is the basis on which the Belfast Agreement is proceeding, but the nationalist majority on the council have decided to engage themselves in an exercise of crude majoritarianism, and that is extremely contrary to the spirit and letter of the agreement," he said.
Mr Trimble, who was speaking after addressing members of the Thornhill College Politics Society, said the decision to change the city's official name was a deliberate attempt to repudiate 400 years of history.
""This decision will certainly change the atmosphere radically. It is an exercise of crude sectarian triumphalism, and we are getting that from people with whom in the past we have worked in the Assembly and in which we would hope to work in the future.
"But following this decision, there will be people who will feel that the mask has slipped, and behind the reasonable exterior we have seen crude naked sectarianism at work. That is bound to affect the atmosphere, and it may even impact on what happens over the next few weeks and months," he said.
The Ulster Unionist Party leader said that while he was not surprised that the main mover behind the name change was Sinn Féin, he was "surprised and disappointed" at the failure of the SDLP to "resist the sectarian impulse that will have far-reaching implications".
Mr Trimble said taking the "London" out of "Londonderry" was an attempt to air-brush Britishness. "John Hume has made a point of recognising both traditions when in the 1960s he held up the name of Londonderry as an example of how both cultures could be recognised. In proposing this change, the council is rejecting John Hume's example," he said.
However, the SDLP leader, Mr Mark Durkan, accused Mr Trimble of "lecturing" and said it was "a very personal issue" between him and Mr Trimble.
"We had a meeting of the Executive here in Derry. Martin McGuinness and I as two local ministers were there as well as the other ministers. We could not get a press release on the meeting that used the word 'Derry' because David Trimble said 'No, the official name is Londonderry. The legal name is Londonderry. That is the only word that will appear on the press release'."