Border Force staff at the U.K. border in Portsmouth | Matt Cardy/Getty Images Post-Brexit customs costs for business could hit £9 billion: report Institute for Government outlines the extent of the UK Brexit customs problem.

The U.K. government faces a mammoth task to prepare the country for customs procedures after Brexit as 180,000 traders face making declarations for the first time, according to a new report from the Institute for Government think tank.

It says businesses face potential costs of between €4 billion and €9 billion, and there is little to indicate the U.K. will be ready to undertake a successful exit from the EU customs union.

Coordination will be a major problem, it states, with over 30 government departments, 100 local authorities and hundreds of private companies involved in the movement and regulation of goods between Britain and the Continent.

Meanwhile, there is almost zero chance of delivering new technology or physical infrastructure before March 2019. The U.K. already lags behind on a planned upgrade to its online customs system, the report says, and ports such as Dover and Holyhead lack the space for major expansion even if time were available.

"Some ministers are placing a lot of faith in innovative new technology — this is not viable, at least in the short term," the report states.

Highlighting that ports on the Continent including Calais, Dunkirk and Rotterdam will need to be onboard with any new arrangements, the report recommends the U.K. government begin a tour of national capitals to get governments on side.

In its position paper on post-Brexit customs, released in August, the U.K. said it hoped to ensure that cross-border trade remains "as frictionless as possible" beyond March 2019.

While the EU has refused to touch on a future trading relationship before divorce talks are finalized, its position paper released last week said the U.K. must ensure that goods on the market before Brexit day continue to be treated under EU rules.

Business groups said they welcomed the report's insight into the problems that lie ahead. "The vast majority of small businesses that trade will need proper time and support to adjust," said Mike Cherry, national chairman for the U.K.'s Federation of Small Businesses.

“The first step to achieving this will be agreeing a transitional arrangement with the EU," he said, adding that the U.K. government must "be clear about when and how [businesses] must adapt."