A WHITEHALL leak claiming Britain will be worse off outside the European Union was yesterday slapped down by a minister as a plot to wreck Brexit.

Steve Baker attacked previous official forecasts and singled out the Bank of England for peddling illfounded doom during the referendum campaign.

The Brexit minister, who confirmed a leak inquiry will be held, told MPs during an emergency statement: “The article is a selective interpretation of a preliminary analysis.

“It is an attempt to undermine our exit from the European Union.”

A row erupted after the BuzzFeed News website published a leaked paper forecasting the impact of three different Brexit scenarios and claiming economic growth after 15 years would be between two and eight per cent below previous predictions.

The detriment depended on whether Britain left with no deal – the worst case – or with a full trade deal with the EU, or the least damaging option with membership of the European Economic Area safeguarding access to the single market.

The Government insisted the work was partial and incomplete and that it also did not explore the impact of the unique and unprecedented deal which Theresa May intends to strike with the EU.

The Prime Minister hammered home to ministers at their weekly Cabinet meeting that the documents were just “initial work, not approved by ministers, and which only considers off-the-shelf scenarios.

“No analysis was made of the bespoke agreement we seek as a matter of Government policy as set out in the Florence speech,” said a Downing Street spokesman.

Labour will today use parliamentary procedure to try to force the Government to publish the full assessment, using the same ruse it successfully employed last year to demand the release of papers.

Some pro-Remain Tories have joined in calling for the analysis to be released.

Mr Baker promised the Government would give MPs “appropriate analysis” before they voted on the terms of the final EU deal once it is negotiated.

But it would undermine Britain’s negotiating hand and “harm the national interest” to reveal ongoing research during talks with Brussels – and no EU country would do the same, he told MPs.

The leaked research also did not forecast the Government’s preferred outcome, was part of a “continually evolving” process and also aimed to “improve on the flawed analysis” of the Remain camp during the 2016 referendum.

Ministers in his department had only just been consulted on it “and we’ve made it clear it requires significant further work. In fact I only saw this report myself this morning”.

Downing Street later declined to endorse Mr Baker’s view that the leak aimed to damage Brexit, with a spokesman telling journalists: “You wouldn’t expect me to attempt to give a view on the motivation.”

But in the Commons some pro-Brexit MPs warmed to Mr Baker’s theory. Tory Philip Davies blamed the research on “some London-centric Remoaners in the civil service” who did not want us to leave the EU.

He said: “They are regurgitating some dodgy figures to try to reverse the result of the referendum.” Labour MP Kate Hoey suggested that “perhaps the person in the Whitehall establishment who leaked this document would be better off moving, and working in Brussels”.

Mr Baker stressed that even the leaked paper forecast economic growth in all three scenarios.

Citing gloomy Remain camp predictions that had not come true, he urged MPs to display “a healthy scepticism about economic forecasting”. Pro-Brexit Tory MP Peter Bone told Mr Baker: “Do you recall prior to the referendum what became known as Project Fear when everything was going to go wrong if we voted to come out – something short of Bubonic Plague – but that did not happen.

“With those warnings, the British people still voted to come out, so of what relevance is another forecast now that predicts exactly the same as Project Fear?” Mr Baker replied: “Most of us on the Leave side thought at the time that those horror predictions would not come to pass after the vote and, happily, we have been proved correct. I look forward to continuing to prove economists wrong after they make horror story predictions.”

He insisted his problem was with the science of economic forecasting and he was “very proud” of his own officials. But Dave Penman, general secretary of the Civil Service union the FDA, said Mr Baker’s remarks were an “insult” to the “dedicated professionals in his department”.

He added: “The public will rightly ask how this fingers-in-ears approach is supposed to help the country navigate such a complex and unprecedented challenge as leaving the EU.”

Professor Patrick Minford, of the pro-Brexit Economists for Free Trade, said: “The Treasury, together with any others involved in this report, have clearly used the same discredited methods that it used to produce Project Fear. Because of this, their estimates should be disregarded.”

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