Brexit has already caused commercial deals to be either deferred or adversely adjusted for almost 40 per cent of Irish engineers working here or in the UK.
A survey by Engineers Ireland of members working in Ireland or Britain, says that, as a result of the UK vote to exit the European Union, more than a quarter of firms have now altered their plans for hiring new people or for their business investment plans.
Of respondents based in Britain or Northern Ireland, more than two-thirds said they were less likely to trade with the Republic of Ireland because of Brexit.
The survey is one of the first to present a sector specific picture of the immediate fallout from the Brexit vote in the UK last June.
Engineers Ireland director general, Caroline Spillane, said: "The United Kingdom's decision to leave the European Union colours every aspect of Ireland's economic future, and the associated uncertainty and unease is already affecting the business activity of our members across the Republic of Ireland, Northern Ireland and Great Britain."
On the plus side, most respondents were optimistic that the major impact of the Brexit would not be felt for several years. However, nearly a third say they have already felt a slowing down of business as the impact from the vote starts to bite.
Forty per cent said they were proactively changing their business strategy to adapt to the new reality but, so far, only one in 10 has plans to let staff, contractors or suppliers go.
The prospects for a hard Brexit are particularly unwelcome for Engineers Ireland members, with 84 per cent against the idea of strict border controls, arguing that it would affect the ability to work across jurisdictions.
Ms Spillane said it was essential that the Irish Government would work to reduce the impact of collateral damage in any forthcoming negotiations, especially in relation to what she called “vital infrastructure projects” such as the Dublin-Derry road upgrade and the North-South energy and communications interconnectors.
The survey was undertaken last week and involved a sample of 3,000 member engineers.