Labour has said it is “more important than ever” that Parliament is recalled after the government published its no-deal Brexit assessment.
Shadow Brexit secretary Sir Keir Starmer said the Yellowhammer document confirms there are “severe risks” if the UK leaves the EU without a deal.
MPs forced the government to release the file before Parliament was prorogued – or suspended – on Tuesday.
Defence Secretary Ben Wallace said the government was mitigating the risks.
He told BBC Radio 4’s Today programme the planning document only showed what might happen “if the government didn’t do anything about it”.
But he added “lots of measures” were being taken to reduce risks, and the chancellor had “opened his chequebook” for greater no-deal spending.
The planning file was a “living document” and an updated version would be published in due course, he said.
Sir Keir said recalling Parliament would allow MPs “the opportunity to scrutinise these documents and take all steps necessary to stop no-deal”.
His comments followed a ruling by Scotland’s highest civil court on Wednesday that the government’s proroguing of Parliament was unlawful.
The Yellowhammer file, which is redacted in parts and almost identical to a version leaked to the Sunday Times last month, says a no-deal Brexit could lead to:
- a “decrease” in certain types of fresh food and “shorter supply” of key ingredients
- price rises for food and fuel, which would “disproportionately” affect those with low incomes
- “disruption lasting up to six months” potentially affecting medicines and medical supplies
- protests and counter-protests across the UK
- lorries waiting for more than two days to cross the English Channel
The document also says some businesses could cease trading, the black market could grow, and some adult social care providers might fail.
Michael Gove, the cabinet minister with responsibility for no-deal planning, told the BBC the government had taken “considerable steps” to ensure the safest possible departure after a no-deal Brexit in the six weeks since 2 August, the date which appears on the document.
On Wednesday, he said “revised assumptions” will be published “in due course alongside a document outlining the mitigations the government has put in place and intends to put in place”.
However, ministers blocked the release of communications between No 10 aides about Parliament’s suspension.
Mr Gove said MPs’ request to see e-mails, texts and WhatsApp messages from Dominic Cummings, Boris Johnson’s chief aide, and eight other advisers in Downing Street were “unreasonable and disproportionate”.
Publishing the information, he added, would “contravene the law” and “offend against basic principles of fairness”.
The government sought to resist the publication of the Operation Yellowhammer document, but lost a vote on the issue in the Commons on Monday, prior to the suspension of Parliament, so it was compelled to do so.
The six-page document warns of disruption at Dover and other channel crossings for at least three months, as well as “significant queues in Kent”.
On food, the document says certain types of fresh food supply “will decrease” and “critical dependencies for the food chain” such as key ingredients “may be in shorter supply”.
It says these factors would not lead to overall food shortages “but will reduce the availability and choice of products and will increase price, which could impact vulnerable groups”.