A report on the impact in Ireland of the proposed trade agreement between the EU and the US, known as TTIP, says it would add to economic growth, employment and investment, as well as trade.
It says beef production and business services exports are the sectors most likely to be adversely affected by the Transatlantic Trade and Investment Partnership.
Commissioned by the Department of Jobs, Enterprise and Innovation, the impact assessment was carried out by Copenhagen Economics.
It finds that a TTIP deal would disproportionately benefit Ireland, because of this country's very high trade level with the US, which is by far the highest of any European country.
It says a TTIP deal would increase the size of the Irish economy by just over 1%.
Using 2013 GDP of €175 billion as the base, this would mean an increase of €2 billion.
The assessment says this would add between 5,000 and 10,000 jobs in export industries.
It would most benefit manufacturing industry, particularly pharmaceuticals and electronics, the agri-food sector and the insurance industry.
It says the beef industry could lose between €25m and €50m a year due to increased competition from lower cost US beef, but this loss is far outweighed by gains of between €230m and €270m in extra sales for other parts of agribusiness, particularly the dairy sector.
While the services industry as a whole should gain from the deal, business services such as accountancy could see declines.
It says Ireland exported €18 billion worth of goods to the US in 2013, equivalent to 21% of total Irish goods exports, making the US the single largest export market for Irish goods.
Pharmaceuticals account for around 70% of exports to the US.
The US accounts for 49% of all Ireland's trade to countries outside the EU - by far the biggest proportion of any EU country.
The next highest is Britain with just under 20%. The EU average is 16%.
The report says one quarter of foreign direct investment in Ireland comes from the US, and Ireland is the third biggest recipient of US FDI.
Irish Farmers' Association president Eddie Downey said the report identifies the "very negative impacts" the trade deal could have on the country's beef sector.
He said that when these are factored in, the agricultural industry would only see a marginal gain from TTIP.
Mr Downey said the Government must ensure this is addressed in any final agreement that may be reached.
Meanwhile the Small Firms Association has welcomed the report, saying it shows the deal could have disproportionally positive impact on smaller companies.
"By reducing trade and regulatory barriers, it will make financial sense for many more small firms to export to the US and for those already exporting to increase their trade volumes," said SFA director Patricia Callan.
She called for the TTIP negotiations to be concluded as quickly as possible and said it was vital that State bodies prepared the ground so that Irish companies could take advantage of any deal once it is finalised.
Business group Ibec has also called for the TTIP negotiations to be completed as soon as possible, saying it would help reduce tariffs and regulatory burdens for Irish businesses looking to trade in the US.