A post Brexit transition period could last up to four years, Foreign Affairs Minister Simon Coveney has said.
Mr Coveney said the longer the transition period the better from an Irish perspective, but that it "can't go on forever".
"I think when we get to the point of negotiating and debating a transition arrangement, which isn't now, that will be in phase two of the negotiations, I think we'll be talking about a period of somewhere between two and four years. Let's wait and see," the minister said.
The minister said the EU is anxious to deal with the phase one issues first before discussing a transition period.
In her speech in Florence last week, Prime Minister Theresa May set out her plan for a two-year post-Brexit transition period under current EU rules, but again repeated that ultimately no deal would still be better than a bad deal.
The confirmation that Downing Street wants a bridging period that would see the UK abide by existing trading terms will give comfort to businesses here and in Britain fearing a cliff edge exit in March 2019, but could stoke anger among Brexiteers.
On the margins of the third All-island Civic Dialogue on Brexit in Dublin today, Mr Coveney said the European Union will be open to discussing a transition period.
He also said that "sufficient progress" on the main issues - citizens rights, the financial bill and Ireland - has not yet been made.
He said good progress is being made on a deal to maintain the Common Travel Area. He said the "most difficult" issue is the border.
"I think we do need to make more progress around bringing clairty around how we are going to resolve the question of maintaining a largely invisible border on the island of Ireland and maintain the status quo," he said.
He reitereated that it would make it easier if Britain agreed to remain in a customs union with the EU.
"But that is not compatible with some of the other things that Britain has been saying, in terms of their ambitions to negotiate free trade agreements all over the world. We aren't where we need to be on border issues."
He said there is no "road map" to get us where we want to be.
Taoiseach Leo Varadkar told the gathering that the timetable to achieving progress by next month is "challenging".
"While there has been some progress, very significant gaps remain," Mr Varadkar said.