A trade agreement between London and Brussels which came into force on Jan. 1 has meant some companies have had to deal with new bureaucracy and rules.

The Survation survey for London First/EY, conducted in February, found 75% had experienced some disruption, even though 71% said they had felt prepared for the changes.

Almost half, 49%, said they expected that to continue in the long-term while nearly a third said they had stopped trading with the EU and countries not covered by rollover agreements.

The findings echo other surveys which indicate businesses have had difficulties with their supply chains, along with other border and regulatory matters, since the new trading arrangements came into operation.

Prime Minister Boris Johnson has said the disruption is mainly due to “teething” problems which would ease as firms got to grips with the new system.

“It’s clear that the disruptions to UK trade with the EU go beyond teething problems with the new regime,” said John Dickie, Acting Chief Executive of London First.

“If the government is to champion Global Britain successfully, it must redouble its efforts to fix our trading relationship with the EU.”

The survey of 1,040 businesses found 29% of firms reported their cost base had increased, with half of these businesses saying those costs would have to be passed on to customers.

However, 26% reported they had a better understanding of how to access new markets, and 24% saw the new trading arrangements as a chance to diversify their activities.