Explainer-What is at stake in the Swiss-EU trade talks

FILE PHOTO: Switzerland's national flag flies beside the one of the European Union in Steinhausen, Switzerland February 11, 2020. REUTERS/Arnd Wiegmann/File Photo

ZURICH (Reuters) - Switzerland and the European Union have been in talks since March to update their trading relationship after a previous effort foundered in 2021, but Switzerland's concerns about its fast-growing population have complicated the process.

Swiss officials have been seeking to agree terms under which they can control immigration from the EU. EU officials worry that such a concession would encourage member states to seek their own opt-outs and weaken the bloc's single market.