Switzerland immigration referendum
Switzerland votes in referendum on capping immigration Ruben Sprich/Reuters

Swiss voters are to cast ballot in a referendum to put a severe cap on immigration, a move which has been derided by the critics as xenophobic.

Under the banner of saving environment, the Ecopop campaign has been lobbying to drastically curb immigrations levels to about three quarters from its current status.

The new proposal aims to limit immigration to just 0.2% of the entire population, meaning an addition of 16,000 immigrants annually. There are about 8.2 million inhabitants in Switzerland of which nearly a quarter are foreign nationals.

Between 70,000 and 80,000 foreigners per year in the last decade have added to the net immigration growth in Switzerland.

"Uncontrolled population growth in a strictly limited area is impossible without causing irreparable damage to our environment," Andreas Thommen, director of Ecopop said adding that the aim is to keep the population of the non-EU country at 9 million by 2050.

"We don't want to see our countryside covered in concrete because it has to cope with an immigrant population flood. I don't' mind foreigners, but it the numbers that count," said Thommen.

In addition to the domestic proposals, Ecopop also aims at contributing towards controlling population in developing nations by distributing 10% of Swiss government's aid in family planning measures.

This is the second time this year the Alpine nation is going to polls over a referendum on immigration.

However, the opponents of Ecopop group – political parties ranging across the spectrum left to right – have rejected the idea.

"It aims to drastically, linearly and arbitrarily reduce immigration to Switzerland, with absolutely no consideration for the needs of the economy," Christian Lüscher, a lawmaker for the Liberal Party, told AFP.