London - Britain's pointman on no-deal Brexit preparations assured parliament that a leaked government assessment predicting food and medicine shortages was a worst-case scenario whose risks were overblown.
But Michael Gove also conceded that Britain faced "significant challenges" if it left without an agreement with Brussels on October 31, as Prime Minister Boris Johnson warns it might.
"Provided the right preparations are undertaken by government, businesses and individuals, risks can be mitigated, significant challenges will be met, and we can be ready," Gove said.
But a leaked official analysis of the potential impact of a no-deal departure reported by The Sunday Times last month made for grim reading.
Here is what the leak said might happen -- and what Gove said he was trying to do to make sure it never would.
- Government effort -
Ahead of the previous March 29 Brexit deadline, the government set up "Operation Yellowhammer" to prepare for disruption in 12 areas, including food and water supplies, healthcare and transport.
Under the plan, every department has an operational centre -- some staffed 24 hours a day.
Yet Gove admitted that the government was only able to do so much, and that businesses and ordinary Britons had to do their own part.
- Business planning -
The Yellowhammer report found businesses largely unprepared for no deal -- despite a Bank of England survey in March finding around 80 percent judged themselves ready.
The Confederation of British Industry (CBI), the main employers' association, said that many goods firms were now less prepared for a disorderly divorce, warning that stockpiling will be harder in the busy run-up to Christmas.
In services, some stop-gap agreements have been reached on both sides.
"We've signed continuity agreements with countries covering £90 billion in trade," Gove said.
What sectors could be most affected by a no-deal Brexit?
- Vital supplies -
Many drug firms have already built up stocks and changed supply routes to reduce disruption, according to the CBI.
But around 28 percent of food consumed in Britain comes from the EU, and major supermarkets have warned of possible disruptions.
The Yellowhammer dossier warns clean drinking water supplies could be impacted, affecting "hundreds of thousands of people".
"Everyone will have the food they need," Gove said.
British food producers hope for Brexit boost
- Planes and trains -
The EU has agreed to allow flights from the UK into the other 27 member states, but only until March 2020.
The high-speed rail link through the 50-kilometre (30-mile) Channel Tunnel running between Britain and France will be kept open for three months.
The leaked assessment warns of likely passenger delays at the Eurostar station in London and Eurotunnel terminal on England's south coast, as well as at airports.
But Gove pointed to 14 additional travel agreements it has reached with countries outside the EU, including Canada and the US.
What are the main UK-EU train and ferry routes?
- EU citizens' rights -
A key element of the draft Brexit deal with the EU was protecting the rights of 3.5 million European citizens living in Britain, and over one million Brits in the bloc.
Many EU countries have moved to protect Britons' rights anyway, while more than 800,000 Europeans have already received some form of new "settled status" in Britain.
Without a deal, British citizens travelling to the EU will be limited to 90-day stays and subject to tighter passport checks.
Gove said Britain would push EU countries to agree on a long-term fix, including for all British citizens living in the EU.
- Trade and tariffs -
Britain plans to scrap tariffs on most imports, keeping a reduced rate for some agricultural products to protect farmers.
The EU will treat Britain as a "third country" imposing tariffs that are on average low -- around 1.5 percent -- but bigger in certain sectors: for cars, the rate is 10 percent.
Gove said a no-deal Brexit would let Britain focus on striking its own agreements with global powers, something it cannot do under the existing agreement.
Tariffs under a no-deal Brexit
- Northern Ireland -
Britain would not immediately apply customs checks on the border with EU member Ireland, to avoid raising tensions in once violence-plagued Northern Ireland.
But the government's leaked analysis concedes that is "unsustainable" and a hard border would return.
Gove stressed Tuesday that a no-deal exit would only mark the start of negotiations with Brussels aimed at more smoothly unwinding four decades of ties.
"Leaving without a deal does not mean that talks with our European partners end altogether," said Gove.
"We will all want to discuss how we can reach new arrangements on trade and other issues."
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