Exports and imports from Britain to the European Union (EU) fell dramatically during the first month after Brexit, according to the UK's official figures.

Exports of goods to the EU, excluding non-monetary gold and other precious metals, slumped by 40.7 percent in January, the Office for National Statistics (ONS) reported, while imports fell by 28.8 percent. 

The effect of the COVID-19 pandemic on trade makes it difficult to identify the extent of the post-Brexit impact, stated the ONS. But it said there were signs that the Brexit transition period hurt trade at the start of 2021.

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Trade in chemicals was especially weak, reflecting the winding-down of a rush to stockpile pharmaceuticals ahead of the end of the Brexit transition period, the ONS said.

The body highlighted a 64 percent fall in exports of food and live animals to the EU - including shellfish and fish. It pointed to delays caused by red tape reported by the Scottish Seafood Association, with consignment sign-offs reportedly taking six times longer.

"External evidence suggests some of the slower trade for goods in early January 2021 could be attributable to disruption caused by the end of the transition period," the ONS said.

Many companies protected their business, stockpiling goods in late 2020 to avoid any disruption, deepening the fall in trade in January.

The ONS said its separate business survey suggested that trade picked up towards the end of the month.

Earlier this week, the UK delayed the introduction of a range of post-Brexit import checks on goods from the EU by around six months, saying businesses needed more time to prepare because of the impact of the pandemic.

What have the experts said? 

David Frost, UK minister responsible for UK-EU relations

"This month's unique combination of factors made it inevitable that we would see some unusual figures this January. As the ONS has pointed out, caution should be applied when interpreting these statistics. 

"The latest information indicates that overall freight volumes between the UK and the EU have been back to their normal levels for over a month now, ie since the start of February."

Ana Boata, Euler Hermes, head of macroeconomic research

"While changes in data collection limit historic comparisons, the significant slump in UK exports of goods to the EU, particularly compared to non-EU trade, provides an ominous indication of the damage being done to post-Brexit trade with the EU by the current border disruption.

"Continued coronavirus restrictions and the unwinding of Brexit stockpiling also added to downward pressure on trade between the UK and EU in January.

"The practical difficulties faced by businesses on the ground go well beyond just teething problems and with disruption to UK-EU trade flows persisting, trade is likely to be a drag on UK economic growth in the first quarter of 2021."

Allie Renison, Institute of Directors, senior policy advisor  

"Even taking account of the December start to lockdown and stockpiling increase in the months leading up to January and Brexit proper, these figures are horrendous. 

"The fact that services trade was far less affected and goods exports to non-EU rose marginally all in the same period reflects the particular impact that disruption from new Brexit changes has had.  

"The IoD long warned of the potential for a perfect storm of variables to collide in giving businesses so little time to adapt to new trading arrangements with the EU. Unfortunately that seems to have come to pass." 

Suren Thiru, head of economics for the British Chambers of Commerce

"The significant slump in U.K. exports of goods to the EU, particularly compared to non-EU trade, provides an ominous indication of the damage being done to post-Brexit trade with the EU by the current border disruption… The practical difficulties faced by businesses on the ground go well beyond just teething problems."

Richard Hunter, Interactive Investor, head of markets 

"It is too early for a definitive read of the Brexit effect, with some evidence of stockpiling ahead of the deadline and signs of some recovery towards the end of the month indicating that the picture could be rather more positive after the initial dust has settled."