Plans to check if hauliers have the correct paperwork to cross the Channel in the event of a no-deal Brexit have been questioned by the government’s spending watchdog.

The National Audit Office has raised concerns about the preparations that have been made to carry out mandatory checks on the M20 and at Manston airfield.

It says that the plans to divert HGVs who do not have the correct paperwork “would be challenging to operate” and that there “is very limited time for the government to get the necessary infrastructure and resources in place to undertake these checks in advance of October 31.”

The report also flags up worries expressed by public authorities that there has been too little information about how the checks would work and the 24-hour period in which hauliers would have to obtain the correct documentation.

As many as 3,000 lorries a day could be diverted to different “turned back sites” in Kent, according to the Department for Transport.

The 71-page report also warns that delays could be caused by EU member states who are likely to introduce “controls which would significantly reduce the flow of traffic able to cross the border.”

It concludes: “Despite the government’s actions, it has been unable to mitigate the most significant risks to the effective functioning of the UK border in the event of no-deal and the border would be ‘less than optimal’.”

It repeats earlier warnings that “it is likely that organised criminals and others would quickly exploit any perceived weaknesses, gaps or inconsistencies in the enforcement regime.”

Concerns are raised about the government’s information campaign, with groups representing traders and businesses questioning “the scale and complexity” of the task they faced.

According to figures provided by HMRC as few as one in 10 of the traders who may need to make customs declarations on the first day of a no-deal Brexit have registered to do so as required by the government.

Of 150,000-250,000 traders who may need to make a customs declaration for the first time, about 25,000 had signed up to the transitional simplified procedures.

Meg Hillier, the Labour MP who chairs the public accounts committee, said the report showed the government was not prepared for a no-deal Brexit.

“It confirms that many traders and businesses will not be ready for new customs and regulatory controls and that organised criminals and others could exploit gaps,” she said.

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