DUBLIN (Reuters) – Irish goods imports from Britain fell by 65% in January from the same month last year as traders grappled with new customs requirements, COVID-19 restrictions and pre-Brexit stockpiling, Ireland’s statistics service said on Thursday.

The value of imports from Britain, not including the British region of Northern Ireland, fell to 497 million euros ($593 million) in January from 1.403 billion euros in January 2020, the Central Statistics Office (CSO) said.

That pushed the proportion of Irish goods imports from Britain to 9% in January, the first month under a new post-Brexit trading relationship, from 21% a year ago, the data showed.

Factors reported by traders included “challenges of complying with customs requirements … stockpiling of goods … substitution with goods from other countries” as well as COVID-19 restrictions, the CSO said in a statement.

The fall was driven by a 75% drop in imports of food and live animals and a 71% decline in imports of mineral fuels, such as petroleum and natural gas. Imports of chemicals and of machinery and transport equipment also both fell by more than half.

Imports from Northern Ireland, which remains in the European Union’s trading orbit under the Brexit withdrawal agreement, increased to 177 million euros from 161 million in January last year, the CSO said.

The data comes after the United Kingdom, including Northern Ireland, last week reported goods exports to the EU slumped by 41% in January compared to December, including a 64% fall in exports of food and live animals to the EU.

Britain’s Office for National Statistics said at the time that COVID-19 restrictions made it hard to quantify how much of the impact was due to Brexit.

Irish goods exports to Britain declined 14% year-on-year in January to 946 million euros. Exports to Northern Ireland increased to 199 million euros from 170 million the previous January.

($1 = 0.8384 euros)

(Reporting by Conor Humphries. Editing by Larry King and Mark Potter)