A new survey has found that optimism among Irish businesses is at its lowest level since 2014 as the ongoing uncertainty surrounding Brexit continues to erode the confidence of companies here.

BDO's Quarterly Optimism index monitors business sentiment among Irish companies.

It shows that 59% of Irish businesses are concerned that Brexit will have a negative impact on their business.

This is up from 42% this time last year. 

It also reveals that the proportion of businesses that see Brexit having a "very negative impact" has doubled from 6% to 12%.

Brexit is having a negative impact on sentiment across all industries and businesses of all sizes, with the retail and wholesale trade industry expecting to be hit the hardest. 

But despite the negative outlook for the months ahead, business activity levels remained steady during the fourth quarter of 2018. 

35% of business reported a similar level of performance to the same time in 2017, while 49% actually reported improved levels of activity. 

BDO said this finding has also been echoed across Ireland, with companies based in Dublin and the rest of the country reporting similar levels of performance and activity.

However companies that rely on exporting have found the current business environment challenging, with overall activity at these companies on a downward trajectory since 2015. 

22% of exporting companies reported lower levels of business activity in the fourth quarter, today's survey showed. 

Meanwhile, employment levels have remained steady, with 78% of businesses maintaining the same staff numbers compared to the same time the previous year.

BDO noted that mid to large sized companies are driving employment growth, with 36% of companies in this bracket reporting higher staff numbers.

Michael Costello, Managing Partner at BDO Ireland said, that he expects the next quarter to be a particularly challenging time for businesses that rely on exporting their products or services. 

"While we hope a no-deal Brexit is avoided, our advice for Irish businesses is to make sure that they have a contingency plan in place and ready to implement, as failure to prepare in advance could have a significant impact in the until a long-term agreement is reached between the UK Government and the EU," Mr Costello added.