Sources said the “Yellowhammer” dossier predicting food, fuel and medicine shortages, as well as chaos on the Irish border, was designed to damage Prime Minister Boris Johnson as he heads to Paris and Berlin for talks this week. They said: “This document is from when ministers were blocking what needed to be done to get ready to leave and the funds were not available. It has been deliberately leaked by a former minister in an attempt to influence discussions with EU leaders. Those obstructing preparation are no longer in government, £2billion of extra funding has already been made available and Whitehall has been stood up to actually do the work through the daily ministerial meetings. The entire posture of government has changed.”
The leak was blamed on a rebel alliance of former ministers led by ex-Chancellor Philip Hammond.
Leading Eurosceptic ex-Cabinet ministers said it was part of an establishment plot to derail Brexit and scare the public.
Yesterday, furious ministers took the unusual step of commenting publicly on the leak.
Michael Gove, who is responsible for no-deal planning, said: “Yellowhammer is a worst-case scenario. Very significant steps have been taken in the last three weeks to accelerate Brexit planning.”
Business minister Kwasi Kwarteng said the “scale and intensity” of no-deal preparations had increased under Mr Johnson and the country would be “fully prepared” for Britain’s EU departure on October 31.
“I think there is a lot of scaremongering around. I think a lot of people are playing into Project Fear,” he added.
Doomsday claims by officials on Operation Yellowhammer preparations for no deal were leaked to a Sunday newspaper.
They said the Government expects the return of a hard Irish border, which could spark protests, road blockages and direct action.
The dossier also warned of significant problems at ports for up to three months, passenger delays at airports and rail links to France and possible disruption to medical supplies.
Fresh food supplies would be hit and the cost of produce set to rise, according to the papers.
Petrol import tariffs would “inadvertently” lead to the closure of two oil refineries, while protests across the UK could “require significant amounts of police resources”.
Gibraltar could face delays of up to four hours at the border with Spain for “at least a few months”.
The documents were prepared under the previous administration and presented to new ministers.
But the assessment was immediately rejected because it did not reflect the work being done for leaving without a deal and was also “inaccurate”. It was leaked ahead of Mr Johnson’s planned talks with German chancellor Angela Merkel and French president Emmanuel Macron later this week.
Conservative MP Daniel Kawczynski accused Remainers of “trying to frighten the British people into thinking that there’s going to be some sort of Armageddon” on November 1, the day after Britain leaves the EU.
Tory former cabinet ministers Iain Duncan Smith and Owen Paterson said the disclosure was part of an “establishment” plot to “sow fear in people’s minds” and “obviously Project Fear dressed up”. The Brexiteers said despite including predictions of significant delays at Channel crossings, officials had admitted they had not spoken to French port bosses.
Gibraltar’s government said the Operation Yellowhammer documents were “out of date” and based on “planning for worst-case scenarios”.
Chief minister Fabian Picardo said: “We do not want a no-deal Brexit. We think it is bad for Gibraltar.
“We are, nonetheless, now ready for it.”
During a visit to Corby, Northamptonshire, today, Labour leader Jeremy Corbyn will threaten to “do everything necessary” to stop a no-deal Brexit.
Mr Johnson has faced calls from more than 100 cross-party MPs to recall Parliament and let it sit permanently until Britain’s scheduled EU departure.
A letter was signed by Tory former ministers Dominic Grieve and Guto Bebb, the Westminster leaders of the SNP, Liberal Democrats, Plaid Cymru, Change UK, the Green Party’s Caroline Lucas and several Labour MPs.
They told Mr Johnson: “We face a national emergency, and Parliament must be recalled now in August and sit permanently until 31 October, so that the voices of the people can be heard, and that there can be proper scrutiny of your government.”
