The new leader of Sinn Fein has said the Supreme Court's Brexit ruling ignores the will of the people of Northern Ireland.
The devolved assembly will not have to be consulted when Parliament votes on triggering EU exit negotiations by the end of March, the Supreme Court concluded.
Michelle O'Neill called on the Irish Government to help secure special status for Northern Ireland within the EU once the UK leaves - despite Britain's highest court rejecting that argument.
"Clearly the ruling again ignores the will of the people of the North who voted by a majority to stay in the European Union," O'Neill said
In its judgment, the Supreme Court unanimously ruled not only did devolved bodies have no role in deciding the future of the UK as a whole in the EU, Northern Ireland had no special status beyond this either.
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The judges found, while Northern Ireland's people had a fundamental constitutional voice on being part of the UK, that did not extend to being part of the EU.
Mrs O'Neill spoke to Irish foreign affairs minister Charlie Flanagan on Monday night and reiterated her view that Northern Ireland must look after their own interests.
"We believe that the North needs to have designated status," she said.
"Clearly the onus is now on the Irish Government to step up to the plate.
"They need to act in the interests of all the citizens of this island because they will be at the negotiating table and it is important that they act in our interests and make sure that we do receive special status given the nature of where we are here."
Northern Ireland voted to remain in the EU referendum by a majority of 56 per cent to 44 per cent.
Mrs O'Neill said Brexit would undermine the 1998 Good Friday Agreement which ended decades of violence and the principle of consent to change held by the people of the north.
"The failure to recognise the will of the people of the North is a failure by the Tory government, continually refusing to acknowledge the will of what the people here have asked for.
"Brexit will absolutely undermine the Good Friday Agreement and the principle of consent."
