Ireland's European Commissioner has said Brexit is still a "lose-lose situation" despite the last-minute Christmas Eve trade deal.
Mairead McGuinness warned of the implications for business, trade and fisheries while saying she hopes the agreement will form a positive basis for renewed cooperation with the UK.
The Financial Services Commissioner also said she is confident Ireland will be "the major recipient" of a €5bn EU fund being set up to help member states affected by Brexit.
Foreign Affairs Minister Simon Coveney is due to brief Cabinet today on the deal in a meeting that was brought forward by a day as part of the process of ratifying the agreement.
The deal is set to be voted on by MPs in Westminster on Wednesday.
Ms McGuinness said that the full implications on the future relationship between the EU and UK will only begin to be felt over time.
The commissioner said talks "went to the wire" and described the EU's chief negotiator Michel Barnier as "a superstar", adding: "His deep understanding of Ireland was an immense asset."
She argued that European unity has been given a massive boost by Brexit but suggested the deal "defies the normal gravity of trade talks" where the parties generally want greater co-ordination - not less.
"The EU continues to view Brexit as a lose-lose situation - but we hope this deal will be a positive basis for renewed co-operation," she said.
January 1 will mark a new era of trading with the UK for businesses and it "will be harder" due to increased paperwork and customs checks at EU-UK borders, the Commissioner warned.
"Fortunately on the island of Ireland the Northern Ireland Protocol means there will be no hard Border," she said.
For food sales to the UK she said "the deal is better than no deal" but there will not be unfettered market access.
"The scenes of trucks queuing on UK motorways were a sign of what can happen when the free flow of goods is interrupted," she said, adding: "transport costs will increase."
"Given the 'take back control' narrative from the UK, including control of their waters, it is no surprise that our fishing communities are deeply concerned."
There have been concerns Ireland will face stiff competition from others to secure a decent share of the €5bn Brexit Adjustment Reserve.