TRADERS hoping to pass goods through the UK’s busiest port have been hit by further trouble after the Government's post-Brexit IT system went down.

The issue affects the system which allows firms to electronically submit paperwork before physically moving goods between the UK and EU at Dover, in Kent.

This “Goods Vehicle Movement Service” is expected to be out until at least Monday, Her Majesty’s Revenue and Customs (HMRC) said in a statement.

The customs office further said that companies could provide alternative documentation in order to “ensure minimal disruption”.

The efforts may prove fruitless however, as motorists were already facing queues of more than 20 miles after the suspension of P&O Ferries sailings.

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A 23-mile coastbound stretch of the M20 was closed from junction eight (Maidstone) to junction 11 (Westenhanger) to store thousands of lorries heading for the Port of Dover, causing chaos on surrounding local roads.

The A20 Roundhill Tunnel was closed under the Dover TAP scheme to prevent HGVs jumping the queue.

Shane Brennan, chief executive of the Cold Chain Federation, which represents businesses operating frozen and chilled storage distribution vehicles, told Bloomberg the chaos was “reinforcing for people – particularly the European-based haulage operations – the hassle of dealing with the UK”.

Ashford MP Damien Green called for changes to be made to Operation Brock, the system by which traffic is supposed to be kept flowing in the event of trouble with the border crossing.

He told KentOnline: “What we need is to make Brock work.

“We have established that up until now it does work, even in times of stress, because the motorway is kept open.

“Once you close the motorway it makes it impossible, so the Kent Resilience Forum needs to look at what changes need to happen so Brock can cope with what is a very unusual situation, where more than half of the freight-carrying capacity at Dover has disappeared in one time.”

P&O Ferries announced on Wednesday that it is preparing to resume cross-Channel sailings.

A spokesperson said: “P&O is looking forward to welcoming back vital services and we expect to have two of our vessels ready to sail on the Dover-Calais route by next week, subject to regulatory sign-off, namely both the Pride of Kent and Spirit of Britain between Dover-Calais.”