Enterprise Ireland has approved funding worth €74m to help companies that are most exposed to Brexit.
It believes 25,000 jobs here are vulnerable in the event of a hard Brexit.
Chief executive Julie Sinnamon said the uncertainty surrounding Brexit had already started to damage Irish businesses, some of whom were not able to increase prices to cover the decline in the value of sterling.
The pound fell dramatically after the referendum and has remained under pressure ever since, losing 16pc of its value against the euro since the vote in 2016. Irish firms will have to raise prices in sterling to maintain their profitability, or swallow some or all of the losses.
With British consumer price inflation running at 2.3pc, it appears unlikely they have had much pricing power in the UK market.
The agency said the biggest hit from Brexit would be felt in food and agriculture as a result of tariffs.
In July, it released a survey of more than 2,400 clients which found 85pc were taking Brexit-related action.
Over 2018, companies receiving funding from Enterprise Ireland added a net 9,119 jobs.
Of the jobs created in companies in which it invests, 64pc were outside Dublin, with construction, life sciences and engineering the top sectors.
Enterprise Ireland approves Brexit funds
The value of Irish food, drink and horticulture exports fell 4pc last year on the back of Despite a year of unprecedented global volatility, involving political uncertainty, extreme weather events and continuing currency fluctuations.