The tourism industry wants a State injection of €12m to help it battle Brexit, which it claimed was the biggest crisis facing the sector since the crash.
The Irish Tourist Industry Confederation (ITIC) said the sector must not be "taken for granted" and warned that tourism budgets here have been cut by 45pc over the past six years.
Chief executive of the ITIC Eoghan O'Mara Walsh said businesses were already seeing an impact in terms of the spend by British tourists here.
"Anecdotally, from talking to tourism businesses particularly in the Border regions, and some Dublin businesses, they've seen an impact in the spend of British visitors," Mr O'Mara Walsh said.
"There's the volume in terms of how many people are coming to Ireland, but it's also what do they spend when they're here.
"We do expect both volume and value to decline from the British market, but what you'll probably see is that the value of the spend from British visitors, about €1.3bn, will decline this year."
The ITIC said that last year, two out of every five visitors to Ireland came from Britain.
Tourism overall employs about 220,000 people.
The ITIC said the tourism budget by the State must increase by €12m immediately to allow State agencies to respond to the trading, employment, investment and marketing needs of businesses exposed to Brexit.
"The message that we're trying to get across is that although tourism is doing well, it can't be taken for granted. Proactive Government policies are needed now," said Mr O'Mara Walsh.
"There's no point in waiting six months or waiting 12 months so that we can all see the negative impact of Brexit."
Paul Gallagher, the ITIC chairman, said it wasn't good enough to say the industry had already been given the reduced VAT rate of 9pc, as it was simply in line with most other EU countries.
With a record number of tourists visiting Ireland in 2016 and the number of domestic staycations on the increase, Fáilte Ireland, the State organisation responsible for promoting and supporting the development of tourism in Ireland, is hoping 2017 will be an even better year, according to its marketing director Noel-John McLoughlin