ORGANISED criminals are likely to be “quick to exploit” gaps and weaknesses in Britain’s border controls in the event of a no-deal Brexit, the UK Government’s spending watchdog warned today.

In a worrying report, the National Audit Office made clear many of the necessary changes to maintain tight security might not be ready in time for when Britain left the EU on March 29 next year.

It came after Lynne Owens, head of the National Crime Agency, warned the ability of UK police forces to tackle serious and organised crime could be "significantly impacted" by a no-deal Brexit without tools like the European Arrest Warrant and the shared Schengen Information System law enforcement database.

And the Commons European Scrutiny Committee questioned whether there would be enough time and political goodwill to make the necessary arrangements to avoid large-scale disruption in Britain if there were a no-deal.

In its report, the NAO said even with a withdrawal agreement significant challenges lay ahead to ensure the UK border was fully functioning yet without one there would be no transition period, heralding a sudden change in the UK’s relationship with the EU.

This could result in delays to goods crossing the border, increased opportunities for tax and regulation dodging and less information to make checks of people crossing the border.

Resorting to World Trade Organisation rules in the event of a no-deal would mean new customs controls, tariffs and non-tariff barriers might apply to around £423 billion of trade at the UK border.

This could require government to put in place new systems, upgrade existing systems and make extensive other changes.

The watchdog noted how the Government had decided to prioritise safety and security; the flow of people and goods; and then compliance activity, including the collection of revenue. Contingency plans were also being prepared to manage queues of traffic in Kent and maintain the continued supplies of essential goods and medicines.

But the watchdog’s report warned: “Organised criminals and others are likely to be quick to exploit any perceived weaknesses or gaps in the enforcement regime. This, combined with the UK’s potential loss of access to EU law enforcement and national security tools, could create security weaknesses which the Government would need to address urgently.”

The NAO pointed out how the creation of the Border Delivery Group had improved the Government's understanding of the changes needed but, given the scale of the task, there were inevitably gaps and risks to progress.

It said many of the changes needed to be made by Government in a no-deal scenario might not be ready on time, noting how 11 of 12 critical systems needing to be replaced or changed to manage the border were at risk of not being delivered on time and to acceptable quality.

The report said new infrastructure to track and physically examine goods could not be built in time and, without this, the UK could not fully enforce compliance regimes at the border from day one.

Although the Border Force intended to recruit almost 600 new staff by March 2019, given uncertainties, there was a significant risk it would not deploy all the people it planned to recruit by Brexit Day.

Moreover, the most complex issues relating to the movement of goods at the border, such as between Northern Ireland and the Republic, still needed to be resolved.

Amyas Morse, head of the NAO, said: “Government has openly accepted the border will be sub-optimal if there is no deal with the EU on 29 March 2019. It is not clear what sub-optimal means in practice, or how long this will last. But what is clear is that businesses and individuals who are reliant on the border running smoothly will pay the price.”