BERLIN (AP) — A group representing European carmakers is urging Brexit negotiators to urgently address issues affecting the auto industry and prevent "potentially disastrous implications" for its supply chain.

Britain is due to leave the European Union at the end of March 2019, but its post-Brexit relationship with the EU has yet to be worked out. EU leaders are set to approve an outline for future negotiations with Britain at a summit later this week.

The European Automobile Manufacturers' Association, or ACEA, said Monday it's concerned about whether cars approved by U.K. authorities can still be sold in the EU after Brexit, and vice versa. It called for both sides to recognize each other's vehicle approvals.

It also said that any new customs checks "would add cost, cause delays and threaten productivity."