The U.K. and Japan are close to agreeing on a post-Brexit trade accord, a deal that would replace the free-trade agreement Britain enjoys through its membership of the European Union and avoid the introduction of tariffs next year.

An agreement in principle is expected in coming weeks, according to a person familiar with the U.K. side of the talks, who asked not to be identified because the negotiations are private. The discussions haven’t yet concluded, and some issues still need to be resolved, the person added.

Rolling over a deal with the world’s third-largest economy has been a post-Brexit priority for the U.K., which is trying to preserve and build upon the benefits of the EU-Japan deal signed in 2018. The U.K. will no longer be party to that agreement when the Brexit transition period finishes at the year-end.