Government ministers are refusing to release Brexit studies that are expected to show the UK will gain little from post-Brexit trade deals with the US.

The Independent has leaked analyses dating back as long ago as 2017 into the probable impact on growth from agreements long hailed as the prize for leaving the EU.

One trade expert said they are likely being concealed because they will show the damage from new trade barriers with the continent will far outweigh the gain from other deals.

Alan Winters, professor of economics at the University of Sussex, said: “The entire Brexit debate has been conducted in a great fog of obfuscation”, and Paul Blomfield, Labour’s Brexit spokesperson, said: “These reports must be released immediately.

“If Boris Johnson wants to risk European trade to secure a deal with Donald Trump, we need to know the cost.”

Freedom of information request

A freedom of information request submitted by The Independent was batted back by the Department for International Trade (DIT), who said analysis into other trade deals is “a work in progress”.

It revealed that academics at the Centre for Economic Policy Research had evaluated the benefits from a US deal, an agreement with Japan and from membership of the CPTPP, a trade partnership of 11 Pacific nations, but said the information would not be released because “it relates to the development of government policy”.

“Premature release of this analysis would be detrimental to the progress of future trade discussions once the UK has left the EU,” the department said.

What we gain from an agreement is “a lot small than what we lose from the EU”

Professor Winters, of the UK Trade Policy Observatory at the University of Sussex, said: “If the government thought it had a very strong case that these deals would be big and strong then they would publish these studies.

“It’s an indication that there’s nothing there. To the extent that we have any analysis, it suggests that the benefits of these deals are very small.

“And, with any modelling, what we gain from an agreement with the US and Japan is a lot smaller than what we lose from the EU.”

And Mr Blomfield added: “The government is embarking on the most important negotiations in our postwar history. The British people deserve to know the impact of the decisions being made on their behalf.”

However, a Downing Street spokesperson said: “New FTAs represent a significant economic opportunity. With new freedoms to strike these ourselves, independently, we can open up our markets, increase wages and improve living standards across the UK.”

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