LONDON (Reuters) - Britain's exit from the European Union without an agreement could lead to severe road blockages across the English Channel, which will affect the supply of medicines and some fresh food, official data warned on Wednesday.

The British government published a document outlining its preparations for the EU exit scenario without agreement.

The document says protests and counter-protests will take place across the country, accompanied by a possible increase in public disorder.

The document, which includes the worst that could happen if Britain leaves the EU without an agreement on October 31, said public and business readiness for such an outcome was likely to be weak, partly because of the continuing political chaos in the period. Previous on Brexit Day.

She added that the trucks may have to wait up to two and a half days to cross the English Channel, and that British citizens may be subjected to excessive inspection procedures by immigration authorities at the border points of the European Union.

"The supply of some types of food will be reduced," the document said, and "there is a risk that panic purchases may cause or exacerbate disruption of food supplies."

She said traffic through the English Channel could fall as much as 60% on Brexit's first day without an agreement, and the worst disruption could last for up to three months.

Disable fuel supply
Truck queues could affect deliveries of fuel, disrupting supplies in London and south-east England, and panic purchases could cause supply shortages in other parts of the country, the document said.

According to the document, cross-border financial services will be affected, as will the exchange of information between police and security services.

The report pointed out that Gibraltar may be affected more than the rest of Britain, due to the application of customs control on the border with Spain.

The report also predicted clashes in fishing grounds between British fishermen and their foreign counterparts.

The document was first published in the Sunday Times on August 18. At the time, Michael Goff, the minister in charge of coordinating preparations for Brexit without agreement, said the document was outdated and did not reflect current levels of preparations.

But he said yesterday that the assumptions contained in the five-page document were being reviewed.

Warnings
The warnings put additional pressure on Prime Minister Boris Johnson, who has promised to implement a Brexit by October 31, with or without an agreement with the EU.

The opposition Labor Party said the document confirms the serious risks of Brexit without an agreement.

"It is totally irrational that the government should try to ignore these blatant warnings and prevent the public from seeing the evidence," Labor spokesman Ker Starmer said on Brexit.

He added that Prime Minister Boris Johnson "must now recognize that he was dishonest with the British people about the consequences of Brexit without agreement."

By publishing the document, Goff responds to a request from lawmakers, but he refused to announce advice from government advisers on Johnson's decision to suspend parliament from Monday to October 14.

Scotland's highest appeals court ruled on Wednesday that the decision was illegal, sparking calls for lawmakers to return to work.