The free-trade deals the UK government has agreed to roll over in the event of a no-deal Brexit have been described as "incomplete".
In an appearance on BBC's Newsnight, UK Trade Policy Observatory warned the deals agreed cannot guarantee continued free trade for British companies.
The UK is part of 40 global trade deals as part of its membership with the European Union. And the government has been working to effectively roll over those deals so that they continue when the UK does leave the EU.
Government ministers, particularly international trade secretary Liam Fox, have consistently claimed that these deals will be continued in their entirety. But that appears not to be the case, according to the UK Trade Policy Observatory.
Following its analysis of the eight continuity deals agreed so far, the organisation said there would likely be additional costs and shortfalls for UK businesses. It relates to the UK's future relationship with the EU. Because we do not yet know what trade arrangements will be in place after Brexit, bilateral trade agreements cannot be deemed complete.
Nicolo Tamberi of UKTPO said: "Bilateral negotiation cannot help when the issues are trilateral. Hence the new agreements cannot guarantee 100% continuity of trade for the UK."
A spokesperson from the Centre for European Reform said: "A big part of the problem is that DIT (Department for International Trade) has continually oversold both its capacity to replicate the existing agreements and the nature of those it has managed to replace.
"If the government had been a little more honest from the start, then it might not have come as such a surprise to many people and businesses when they fell short."