Irish manufacturing activity eased as the year drew to a close, with output, new orders and employment growth all slowing, according to the latest report on the sector.

The country's Manufacturing Purchasing Managers' Index was 54.5 in December, down from 55.4 in November and the lowest level in nine months.

The Irish economy was the best performer in the European Union in 2018 for the fifth year in a row, but it is vulnerable to the threat of an unruly exit by Britain from the EU.

The last time the index was below the 50 mark that separates growth from contraction was May 2013.

Underpinning the drop in the headline index was a slowdown in new-order growth among manufacturers to the weakest point in eight months.

The sub-index measuring new orders dropped to 55.1 in December from 57.3 in November.

"Irish manufacturers experienced a slowdown in growth in December, with PMI data indicating weaker rises in output, new orders and employment," said Amritpal Virdee, an economist at IHS Markit, which compiles the Ireland manufacturing survey.

"While some firms saw signs of weaker demand, panellists are confident of a pick-up in the new year, supporting strong growth of purchasing activity and stockbuilding."