What happens when a country decides it doesn't want its population to grow? Swiss voters are set to decide on a referendum proposal that would cap the population at 10 million.

Supporters say rapid growth is putting pressure on housing, transport and public services. Critics argue Switzerland's economy depends on immigration.

If approved, the measure could eventually force Switzerland to end its free movement agreement with the European Union, which is a crucial part of Swiss-European relations.

We look at what's being proposed, why immigration has become such a major political issue, and what the result could mean for Switzerland and the rest of Europe.