A no-deal Brexit could cause cross-border agriculture trade in Northern Ireland to “virtually stop” within 24 hours, according to a leaked UK government document.

The document also says a no-deal Brexit could trigger “consumer panic”, food shortages and an increased security threat within a fortnight.

The slide, prepared for British ministers and obtained by Sky News, says the pound could fall in the first month, while Northern Ireland may face law and order challenges.

Marked “official sensitive” and titled “What this could look like on the ground”, it also warns that UK nationals in the EU could lose access to services and residence rights within the first 24 hours.

The leak on Thursday came as Boris Johnson’s government ramped up its rhetoric over leaving the EU by the October 31st deadline, whether a new exit deal is brokered or not.

And it was revealed as chancellor Sajid Javid announced £2.1 billion of funding to prepare for no-deal.

Bank of England governor Mark Carney also warned that a deal-less break would be an “instantaneous shock” on the economy and cautioned that the pound would fall, inflation would rise and GDP would slow.

A second leaked document, this one from the Cabinet Office and seen by The Guardian, warned of a risk of “panic buying” exacerbating food supply disruption, as well as a threat of civil disorder.

Sky reported that its leaked slide was prepared in the final weeks of Theresa May’s tenure as prime minister.

PA understands the document was shown to ministers but not signed off by the government, meaning it was not official policy.

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Potential friction

The document’s worst case scenarios in the case of no-deal – broken down into first day, first fortnight and first month categories – also included potential friction at sea between UK and EU fishing vessels.

It says that, within 24 hours, cross-border agriculture trade in Northern Ireland “virtually stops” as other trade “slows”.

In the first fortnight column, it details: “Potential consumer panic and food shortages.”

And it warns of a “possible increased risk of serious organised crime, including people smuggling and illegal migration”.

The first month could also see heightened policing resources becoming “unsustainable”, as operational gaps in security “continue to emerge”.

Questioned on the leak, a No 10 spokeswoman said: “We do not comment on leaked documents.”

The prime minister was due on Thursday to chair his first meeting of the Brexit war cabinet – comprising of the chancellor, foreign secretary Dominic Raab, chancellor of the Duchy of Lancaster Michael Gove, Brexit secretary Steve Barclay and attorney general Geoffrey Cox.

On the same day, the Bank of England slashed its growth forecast to 1.3 per cent for both this year and next, down from the 1.5 per cent and the 1.6 per cent previously predicted.

Funding package

Announcing the £2.1 billion funding package, including £1.1 billion already committed to plans for October 31st and £1 billion in reserve, Mr Javid said it was “vital that we intensify our planning” for the Brexit deadline.

Measures in the package include:

– £344 million for border and customs operations;

– £434 million to ensure vital medicines are available;

– £108 million to support businesses, and

– £138 million for a public information campaign to begin in the “near future”

The funding will pay for 500 more Border Force officers, improved infrastructure at ports and extra cash for Operation Brock – the plan to cope with traffic chaos in Kent caused by delays at Dover in the event of no-deal.

Supplies of medicines could be hit by disruption in the event of a no-deal Brexit, so mitigation plans include increased freight capacity, warehousing and stockpiling.

Mr Johnson has ordered planning for a no-deal Brexit to be ramped up, even though he has claimed the odds of it happening are a “million-to-one against”.

He sent his top Europe adviser David Frost to Brussels to deliver his message that the UK will be leaving the EU on October 31st “whatever the circumstances”. – PA