Work on post-Brexit freight software is unlikely to be ready for the 1 January deadline, the Association of Freight Software Suppliers (AFSS) has warned.
The idea behind the new border software is to reduce the time that vehicles would need to stop for border checks.
It is intended to help haulage and logistics companies submit paperwork digitally so that taxes can be calculated.
However, the project has been slammed by the RHA and Logistics UK who claim it will add extra time and cost to journeys made by international hauliers.
In a BBC news report, the AFSS admitted its members could not guarantee delivery of the software because officials had 'failed to give it details and direction'.
Fears are now growing that delays could hamper efforts to get products to retail outlets, forcing up prices.
“This is something we have been pointing out to government for many months," RHA MD for policy and public affairs, Rod McKenzie told motortransport.co.uk.
"It is worrying for traders that this major IT project on which so many businesses – indeed the UK economy – depends on is still not tried, tested and working properly. Time is running out to fix this – but fix it and fast is what everyone wants Mr Gove to do.”
Added Kevin Green, marketing & communications director at Logistics UK: ‘The idea is to minimise the time the vehicles, which currently move seamlessly across the border, would need to be stationary while checks are made on the goods inside them.”
"Having to do so would add delays which add time and cost to the journey and has to be paid for by someone. Logistics operators currently work on very low margins and would not be able to absorb significant additional costs."
HMRC said it was 'continuing to engage extensively with the software developer community and community system providers to ensure that they have everything they need to develop their products'.
The plans include a support service to file customs declarations on behalf of traders, so they will not have to do it directly themselves.
HMRC also said it had contingency plans in place to keep goods flowing.