The SDLP MLA Declan O'Loan has withdrawn a call for the formation of a single nationalist party after there was a furious reaction from colleagues.
Earlier, in a statement not issued through the party press office, he said he had discussed the idea with the grassroots members in north Antrim.
Mr O'Loan said that it was very strongly supported.
But he later withdrew the original statement saying it "does not represent established party policy".
Neither he nor the party are making any further comment but senior sources say the party was "furious" and that Mr O'Loan was "told in no uncertain terms to withdraw the statement".
Earlier the North Antrim assembly member said: "I believe that a major realignment of northern nationalism is now called for and I think that this means the formation of a new single nationalist party.
"The values of the SDLP and its ability to command respect and at least second preference votes across the whole community are not something that should be lost.
"In the interests of achieving Irish unity, that respect is vital."
He added: "Many nationalist voters are willing to exercise their votes interchangeably between the SDLP and Sinn Fein."
Irish News columnist Tom Kelly, a former SDLP vice-chairman, said Mr O'Loan's remarks were "out of character for such a reflective, intelligent guy".
"I think he was probably trying to articulate the fact that he had been receiving feedback on the doors in his constituency, but he took it four or five steps too far," he said.
Sinn Fein's Daithi McKay said Mr O'Loan's comments and subsequent withdrawal of them showed disunity in the SDLP's ranks.
"The comments from SDLP MLA Declan O'Loan in respect of a single nationalist party and his resulting 'gagging' by the party leadership demonstrate that the SDLP are in disarray," he said.
Ulster Unionist MLA John McCallister said: "Declan O'Loan's comments appear to have caused something of a stir in the SDLP."
Gerry Lynch of Alliance added: "People who perhaps thought that the SDLP were opposed to tribal headcounts will be very alarmed at his remarks."