Britain faces shortages of fuel, food and medicine and a likely hard border in Ireland if there's a no-deal Brexit on Oct. 31, according to U.K. government documents leaked to the Sunday Times.

Why it matters: The Cabinet Office forecast outlines the most likely aftershocks of a no-deal Brexit rather than a worst-case scenario, according to the news outlet.

The forecast comes as the Telegraph reports that Prime Minister Boris Johnson will tell German Chancellor Angela Merkel and French President Emmanuel Macron this week that the British Parliament can't stop Brexit.

What they're saying: Current plans to avoid widespread checks will prove unsustainable, making a hard Irish border likely, according to the Cabinet Office leak.

The Cabinet Office estimates up to 85% of trucks using the main crossings in the Channel that separates Britain and France "may not be ready" for French customs, potentially causing up to 3 months of disruption at ports, per the Sunday Times.

The big picture: Johnson is due to meet his European counterparts ahead of a G7 summit on Aug. 24–26 in Biarritz, France, in what will be his first trip abroad as leader, per Reuters.

The Telegraph reports that its former regular columnist Johnson is expected to tell Merkel and Macron "that they have two months to agree a deal acceptable to the cabinet and parliament, without which the UK will exit without an agreement on Halloween."

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