Impact of Brexit on both sides of border probed at Belfast and Dublin events
Work will be required to convert the "too good to be true" language surrounding the border into an actual agreement, a Brexit event in Belfast has heard.
And Johnny Hanna, partner and head of tax at business advisers KPMG, warned that some firms were at a "tipping point" in their Brexit plans as he addressed a breakfast held by Belfast Telegraph sister publication Ulster Business.
And in Dublin, Belfast Telegraph publisher INM hosted a Brexit breakfast at Trinity College attended by Taoiseach Leo Varadkar.
Mr Hanna told business people at the event in Belfast's MAC: "I think everyone recognises that solving the border problem, and actually converting that 'too good to be true language' into the actual agreement itself, will require a lot of work."
The event also heard from Ryanair chief marketing officer Kenny Jacobs.
Mr Hanna said uncertainty remained despite some positive statements made by Westminster and the EU, over areas such as workers' rights and the common travel area.
"There are some very positive statements in regards to EU nationals," he said.
"There are some question marks around those EU nationals who arrive in the transition period, assuming there is one, and also some question marks around the common travel area.
"We are getting close to a tipping point for many businesses in terms of having plans in place and press the button on those plans."
Mr Jacobs warned that Brexit could create turbulence for aviation. He said flights could stop in April next year, as there was nothing in place to replace the 'open skies' agreement allowing air travel between EU countries.
"It's as simple as this. Open skies is the agreement that allows European member states to fly among each other," he said.
"The UK Government has said we are coming away from Europe, leaving the European Court of Justice, but the ECJ governs open skies.
"So, as it stands today, on April 1, 2019, Britain will leave the European Court of Justice (ECJ), and open skies will no longer operate. That is simply what we are looking at."
Meanwhile, Mr Varadkar told INM's Brexit breakfast that a draft text of the withdrawal agreement between the UK and the EU would be published within two weeks.
But he added: "As Chancellor (Angela) Merkel said, the UK can have as close a relationship with Europe as it wants to have. What it can't do is cherry pick. The EU is a set menu restaurant, not an a la carte."
The Taoiseach said the UK can't simply continue to take the benefits of the EU after Brexit.
"If you're a member of the club, you're a member of the club. And if you want to be an associate member, you can't write the rules yourself. That is a circle that still needs to be squared."