The Taoiseach is reassuring unionists in Northern Ireland that the proposed new Brexit deal will not undermine the integrity of the UK.

The new Brexit Withdrawal Agreement will be debated at a special sitting of the House of Commons tomorrow.

It was approved by the European council yesterday following marathon talks between the European Union and United Kingdom in Brussels.

It remains unclear whether the UK Prime Minister Boris Johnson will have the numbers to get it through the House – with the Democratic Unionist Party insisting they will not support it.

Speaking as the EU Leaders Summit came to a close in Brussels today, Leo Varadkar said the deal respects the constitutional position of the North in the UK.

“If this is ratified and fully implemented, the queen will still be the queen, the pound will still be the pound and people will still post letters in Royal Mail red letterboxes,” he said.

“Northern Ireland will still be part of the UK and because of the Good Friday Agreement that is protected – until such a time, should that time ever arise, where the majority of people in Northern Ireland vote otherwise.”

A Seagull looks towards Britain's Parliament buildings in London, 18-10-2019. Image: AP Photo/Kirsty Wigglesworth

He noted that there is nothing new in the North following different rules to Britain.

“It’s been the case for 100 years now that Northern Ireland has its own legal system, has a different education system, has lots of different laws, lots of different rules from the rest of the UK,” he said.

“And that’s a reflection of devolution and autonomy and doesn’t change the constitutional position of Northern Ireland.”

British Prime Minister Boris Johnson attends a press conference during an EU summit in Brussels, 17-10-2019. Image: Xinhua/Zhang Cheng

He warned UK MPs not to bank on any Brexit extension if the vote the deal down – and said he believes this will be the final offer from the EU.

“I cannot see the EU coming back again for another set of negotiations – I really can’t,” he said.

“I think the EU has been really responsible over the past couple of years. We have negotiated one deal that was rejected three times by the House of Commons.

“We now have a revised deal, so now it back over to the House of Commons and the European Parliament to make the final decision on this.”

The UK Labour Party, the Liberal Democrats and the SNP have all said they will not back the deal.

However, a number of Tory MPs who refused to back the original agreement brought home by former Prime Minister Theresa May have indicated they could support the new plan.

Efforts to win the support of Labour MPs representing constituencies that voted for Brexit in the 2016 referendum are likely to intensify in the coming hours.

Mr Johnson needs 320 Commons votes to pass an agreement, presuming every MP uses their vote.