Switzerland is holding a controversial referendum on Sunday to decide whether to cut immigration by about 75%.

According to supporters, the move would help protect the environment by reducing the need for new transport links and new housing.

Opponents, including the government, all political parties, employers and unions, argue the proposed cap on immigration growth at 0.2% of the population, or an addition of around 16,000 people per year, will hurt the Swiss economy by curbing the possibility for Swiss employers to recruit skilled foreign labour force.

Besides, opponents claim, capping immigration would derail Switzerland’s agreements with the EU on free movement of labour.

Swiss statistics put the number of foreign nationals, most of them from EU member states, at about 25% of the country’s population of around eight million.

Under Switzerland’s system of direct democracy, citizens can force a referendum if they gather enough signatures of support. If an initiative wins approval at a referendum, it must become law within three years.