A trade deal between Europe and the US will boost the economy by just over 1pc, or roughly €2bn, a report commissioned by the Government claims.
Exports and imports will both surge by about 4pc, and up to 10,000 jobs in exporting sectors are are forecast, according to the study by economic consultancy firm Copenhagen Economics.
Negotiators are working to reach a deal on a Transatlantic Trade and Investment Partnership, generally known as TTIP.
It is primarily an agreement to cut tariffs and regulatory barriers to trade between the US and EU countries, but has encountered opposition from certain quarters of society across Europe, including trade unions.
The report, to be launched today by Jobs Minister Richard Bruton and EU Commissioner for Trade, Ceclia Malmstrom, also claims that real wages will improve, on average by 1.5pc, for all skill groups.
Sectors expected to gain from any deal include pharmaceuticals and chemicals, electrical machinery, agri-food, particularly dairy and processed food, and insurance, the study finds. But it notes there may be negative consequences for the beef sector, the most vulnerable sector, including a possible loss of jobs.
The report warns that beef producers should prepare for more competition from cost-efficient US beef producers in the European market. The size of the negative impact on the sector is potentially €25m to €50m.
However, it is believed a deal is beneficial overall for agriculture, amounting to up to €270m, with dairy expected to be the biggest winner.
There are also possible negatives in the services sector, particularly around ICT.
However, Mr Bruton said the benefits of a deal are "overwhelmingly positive".
"There is a lot of complexity and a lot of competing claims being made about TTIP," he said. "As with any trade agreement, there are some sectors which will benefit and some areas where challenges may emerge, and we will work hard to address those challenges."
The projected one-off 1.1pc increase in GDP is expected to materialise within three to five years of a deal being sealed.
2015 is crucial in making progress on TTIP before President Barack Obama leaves office, but so far nothing has been agreed. Each side has accused the other of trying to protect specific industry interests. Free-trade advocates say the agreement will create a market of 800 million people, generate millions of jobs and serve as a counterbalance to Russian and Chinese power.
Those opposed say it will undermine European laws and allow US multinationals to bully EU governments into doing their bidding.
Sinn Fein MEP Matt Carthy accused the Government of spin. "There are widespread concerns among civil society, trade unions, the agricultural sector, environmental groups and other NGOs in Ireland and across Europe in relation to this trade deal," he said.
"They are concerned about the lack of transparency surrounding the negotiations, they are concerned about the potential impact this agreement could have on their sectors and they are concerned about power being given to large corporations at the expense of citizens and democracy."