Sinn Féin is embarking on a Europe-wide “diplomatic offensive” to convince political leaders of the case for Northern Ireland retaining special EU status post Brexit, the party’s leader in Northern Ireland Michelle O’Neill has said.

Unveiling her party’s candidate line-up for March’s Assembly election, Ms O’Neill said she had written to the 27 other states to lobby for their support.

She was heavily critical of Northern Ireland Secretary James Brokenshire’s comments last week, when he ruled out any suggestion that the region could retain some form of EU designation after the UK leaves the union.

“I have got news for you James, it won’t be your decision; it will be the other member states who decide the terms of Brexit,” Mrs O’Neill said at the event in Belfast.

“That is why I have today written to all the European leaders setting out our case.

“That is why Sinn Féin is on a diplomatic offensive across the length and breadth of Europe, where there is a hell of a lot more sympathy for our case than for the right wing, anti-immigrant agenda which has fuelled the Brexit fiasco in the first place.”

Mrs O’Neill called on “all pro-Remain parties” to join the Sinn Féin campaign.

Warning of the consequences of Brexit, the Sinn Féin leader said the snap poll in Northern Ireland and the political negotiations set to follow it had ensured “we are playing for the biggest of stakes”.

The Mid Ulster candidate repeated her criticism of her erstwhile partners in government, the DUP, in particular the party’s handling of the botched Renewable Heat Incentive (RHI) affair.

She said the decision of former Sinn Fein deputy first minister Martin McGuinness to quit the powersharing executive, forcing DUP first minister Arlene Foster from her post, was a “watershed in Irish history”.

“When Martin McGuinness stepped Arlene Foster aside it was clear demonstration to those in the DUP who still pine for one party unionist misrule that those days are gone,” she said.

“Sinn Féin will never tolerate the kind of arrogance and contempt for the public which the DUP have displayed.

“We won’t tolerate racism, sectarianism, homophobia and sexism - we won’t tolerate scandal, corruption and the abuse of public funds.

“If the DUP ever wish to hold ministerial office again, they are going to have to learn that lesson.”

Sinn Féin president Gerry Adams also attended the candidate launch in the Waterfront Hall.

He accused the DUP of threatening the existence of the powersharing institutions.

“The future of the Good Friday Agreement, the political institutions it created, the principles of equality and respect and parity of esteem that should underpin them are at grave risk,” he said.

PA