The Taoiseach has reiterated that Brexit is not an Irish or European Union policy, but a British one.
Speaking during Dáil statements on the UK's exit from the EU tonight, Enda Kenny said the Government believed it is bad for Britain, for Europe and for Ireland.
He said it challenged Ireland's peace and prosperity.
He said Ireland would be negotiating from a position of strength, however, he said Ireland would maintain its close relationship with Britain.
Mr Kenny said Ireland's unique concerns and circumstances to support and protect the achievements, benefits and commitments of the peace process; to avoid a hard border and protect the common travel area were reflected in the EU negotiating guidelines published last month.
He said it was by no means a given that Ireland would be seen as a priority in the negotiations, but it has come about "thanks to the strategic, persistent and patient work" with the support of European partners.
The Taoiseach said the statement agreed by the European Council acknowledged that in the event of a united Ireland brought about in accordance with the Good Friday Agreement, the entire territory of such a united Ireland would legally be part of the European Union.
"This provides reassurance on this aspect of the Good Friday Agreement, regardless of the status of the UK within the European Union", he said.
He said in terms of the Article 50 process it was vital that the process would be done in an orderly manner and as part of the EU 27 the Government would vigorously pursue and defend national interests.
The Taoiseach said the Government has made it clear there will be no visible hard border on the island and will ensure the protection of the rights of those in Northern Ireland who choose to exercise their right to hold Irish and thus EU citizenship advocating continued EU engagement in Northern Ireland.
The Government is working on the economic implications of Brexit, he said, telling the Dáil it will draw on the work to date across departments.
Amongst the matters being looked at according to Mr Kenny is to ensure sustainable fiscal policies in order to respond to potential shocks; policies to make Irish enterprise more diverse and resilient; to diversify trade and investment patterns as well as strengthening of competitiveness.
He said it was essential that the Government ensure that the economy is Brexit ready and in that context he noted Ireland's bids for the two EU bodies currently located in London - the European Medicines Agencies and the European Banking Authority.
"I believe that Ireland would be an outstanding location for each of these agencies particularly when the priorities to ensure both a smooth transition from their current location and a sustainable path for them".
He said the decision would be made in the Autumn by the European Council and Ireland is in competition with quite a number of other countries for the two agencies.
Govt playing 'catch up' - Martin
Fianna Fáil leader Micheal Martin said there was no evidence of the Government seriously engaging on Brexit under after the referendum and they were now playing "catch up."
He said Ireland had core strengths built up over decades, but these would not be enough to avoid a dramatic economic disruption.
He said the Government had to move from general statements to specific proposals.
Sinn Féin leader Gerry Adams said the Government should be seeking special status in the EU for Northern Ireland.
Mr Adams said the draft negotiations published by Michel Barnier were "vague and aspirational."
He said this was not the fault of Mr Barnier, who was well disposed to Ireland, but that of the Taoiseach.