LONDON (AP) — Lawmakers scrutinizing Britain's exit from the European Union say progress in trade talks with the bloc is "highly unsatisfactory," and that the country may have to stay in the tariff-free EU customs union for years after Brexit.

The Exiting the European Union Committee says in a report Thursday that time is running out to set up new trade arrangements, and staying in the customs union may be "the only viable plan."

Britain is due to leave the EU in March 2019, followed by a 20-month transition period. The committee says it's unlikely new customs procedures will be ready by the time the transition ends in December 2020.

Committee chairman Hilary Benn says Britain will probably have to remain in a customs union "until alternative arrangements can be put in place."