If approved the proposal would clash with Switzerland’s constitutionally protected right to freedom of religion.

The Interior Ministry said it received a proposal on Tuesday with more than the required 100,000 signatures.

It was submitted by members of the nationalist Swiss People’s Party and the fringe Federal Democratic Union, who say they are acting to fight the political spread of Islam. They argue that the minaret is a symbol of political and religious claim to power rather than a mere religious sign.

People’s party lawmaker Walter Wobmann defended the move, saying the authorization for constructing a minaret in Winterthur near Zurich and pending requests in three other Swiss towns have exceeded the limits of many Swiss people’s tolerance.

“Many recognize in this a further step in the creeping Islamization of Switzerland,” he said.

It’s not the first time the People’s Party has ignited a provocative campaign. Recently they embarked on an anti-immigrant initiative, complete with posters showing a black sheep being kicked off a Swiss flag and dark hands grabbing at a pile of Swiss passports.

Swiss voters last month, however, overwhelmingly rejected their proposal to make it harder for foreigners to gain citizenship.

Still, construction of traditional mosques and minarets in European countries has rarely been a trouble-free affair. Sweden, France, Italy, Austria, Greece, Germany and Slovenia are among the countries which have experienced opposition or protests against such projects.

In Cologne, Germany, plans to expand the city’s Ditib Mosque and complete it with dome and two 54-meter-tall (177-feet-tall) minarets, have triggered an angry response from right-wing groups and the city’s Roman Catholic Archbishop.

Slovenia’s Constitutional Court in 2004 banned a move to hold a referendum on the building of a mosque.

Switzerland’s unique system of grass roots democracy allows political hard-liners to take the issue further than in other European countries, where constitutional courts or governments have blocked moves against mosques and minarets. Any Swiss citizen who collects 100,000 signatures within 18 months can put a popular initiative to a nationwide vote.

No date has been set for the referendum. If it is approved, the Swiss parliament must pass a law enshrining a construction ban in the constitution.

Minarets are tall spires typically built next to mosques where religious leaders call the faithful to prayer. There are currently only two minarets in the country, attached to mosques in Zurich and Geneva. Neither is used for calls to prayer.

Opponents of a construction ban say it would violate religious freedom. More than 310,000 of Switzerland’s 7.5 million people are Muslims, according to the Federal Statistical Office.

A United Nations expert on racism, Doudou Diene, says the campaign is evidence of an “ever-increasing trend” toward anti-Islamic actions in Europe.

The Swiss government is concerned about the impact the referendum will have on its international image. Swiss President Pascal Couchepin said the government will recommend that voters reject the proposed ban. Other members of Switzerland’s cross-party government have also spoken out against the ban.

Foreign Minister Micheline Calmy-Rey has warned that the anti-minaret initiative would lead to a security risk for Switzerland because it could spark Muslim’s anger.

Henri-Maxime Khedoud, spokesman for the Swiss Association of Muslims for Secularism, said that although the Swiss mosques don’t really need minarets, the initiative was an attack against Muslims and contrary to the freedom of everyone to practice his faith.