SINN Féin president Gerry Adams has ruled out ending the party's abstentionist stance at Westminster to take part in a Brexit vote.
Asked about changing party policy, even on a temporary basis, Mr Adams told RTE: "No, and you knew the answer to that before you asked me."
His comments came as party colleague Martin McGuinness said he had "no faith" that MPs would respect the result of the EU referendum in Northern Ireland where 56 per cent voted to remain.
"Who knows where all of this is going to end up," Mr McGuinness said.
"There is absolutely no doubt whatsoever that all of us face immense challenges that lie ahead."
Asked if Sinn Féin would change its abstentionist policy to allow its four MPs to influence a knife-edge vote in the House of Commons, the Foyle MLA said the Labour Party had already stated its intent to respect the outcome of the UK's referendum.
"Brexit will have a massive impact on every one of Ireland's 32 counties," he said.
"So we believe that any decisions that need to be taken about the future of this island [should] be taken between our administration in the north and the government in Dublin."
He added: "As far as I'm concerned, the assembly and the Dáil are the people who make the decisions about the future of the people who live in this island and of course overwhelmingly on this island people see their future in Europe and the referendum result clearly shows that 56 per cent of the people of the north - and that was a cross-community vote - made a very decisive decision that they want their future to be in Europe."
