EU: progress on Ireland is priority
European leaders have agreed that the UK must "sort out" the past, including Anglo-Irish relations, before beginning future trade negotiations.
The blunt warning has propelled Taoiseach Enda Kenny to the centre of today's meeting of the EU Council, where he will seek backing for a series of guarantees relating to Northern Ireland and the movement of goods and people.
In a letter to the 27 heads of state who will attend the EU Council meeting, President Donald Tusk said members must "unite around the principle" progress on people, money and Ireland "comes first".
"Before discussing our future, we must first sort out our past," he said, in a clear signal that he is against British proposals for early talks on trade.
Leaked drafts of the European negotiation paper also show the EU will rule out the comprehensive trade deal that UK Prime Minister Theresa May is looking for - unless she agrees to continued oversight of banks by EU regulators and courts.
The remaining members will also demand Britain pay an exit bill of around €60bn.
Sources said the Government is "increasingly encouraged" by the language from its EU counterparts. The conclusion documents from today's meeting will include an acknowledgement that in the event of a united Ireland the six counties will have to be automatically allowed back into the EU.
"If an official EU document includes a phrase similar to a 'united Ireland' or 'the reunification of Ireland' then that is historic in its own right," said one source.
Public Expenditure Minister Paschal Donohoe said he doesn't believe a border poll is "imminent" but said it's of "imperative importance" that the Good Friday Agreement is "underscored in a post-Brexit legal and political environment".
"We are confident that the conclusions which will emerge from the European Council are going to make reference to the very specific needs that Ireland has in relation to the movement of people, in relation to the Border, in relation to the peace process and in relation to the Good Friday Agreement," he said.
It is also expected that today's meeting will be told of the need to relocate the European Medicines Agency and European Banking Agency from London.
Ireland has bid for both entities, although sources admit it would be a major coup to win either. Health Minister Simon Harris was in Brussels yesterday to canvass support for moving the EMA to Dublin.
He told 25 EU ambassadors that Ireland "represents the best and most sustainable choice for Europe and the EMA".
The minister said Dublin ticks every box in "geographical and cultural proximity for ease of transition".