European companies wanting to export to the UK could end up paying two-and-a-half times more than their British counterparts sending goods the other way, if a new trade bill is not in place by the time Britain leaves the EU.
According to a report by Civitas, EU firms would have to pay £12.9bn ($15.8bn) a year in tariffs to the UK if Britain turned to World Trade Organisation terms after Brexit. However, British companies exporting goods to the EU would only have to pay £5.2bn a year.
The think tank said the figures highlighted the importance of reaching a trade deal agreement in the two-year window that will open once Britain triggers Article 50 to formally begin the exit process from the union.
"These figures highlight the importance of securing a post-Brexit trade deal not just for the UK but also for the EU," said Justin Protts, the author of the study.
"European exporters have a great deal to lose without free trade across the continent. The knock-on effects will harm their ability to sell to the UK."
However, the report added the £5.2bn figure Britain would have to pay for exports is higher than the cost faced by each of the other 27 EU members wishing to export goods to the UK. German and French exports to the UK would face tariffs of £3.4bn and £1.4bn respectively.