Swiss gun rights proponents fear a new European Union measure to tighten gun control could disarm thousands of law-abiding citizens, Reuters reports.

The proposed gun restrictions which Switzerland, a non-EU member, would be obliged to implement under cross border agreements, has raised hackles among the Swiss, who resent intervention from Brussels, the news wire reported.

It also comes at a time of increased tensions between Switzerland and the EU over Swiss efforts to curb immigration.

Christopher Blocher, a leading voice of the Swiss right, told Reuters Switzerland should end its participation in the system of passport-free travel if the tighter gun restrictions are defeated in a referendum.

The proposed measure would curb online weapons sales and impose more restrictions on assault weapons, the according to Reuters. It was drafted after the ISIS terrorist attacks in Paris last November that killed scores of people.

The initial proposal provoked an outcry in Switzerland because it meant a ban on the long Swiss tradition of ex-soldiers keeping their assault rifles, the new wire reported.

Then two months ago, Justice Minister Simonetta Sommagrua returned from meetings in Brussels saying she he successfully negotiated against such a ban, according to Reuters. But in the fine print, the EU demanded concessions including psychological tests and club membership.

Swiss gun rights proponents also fear the restrictions could encroach on the country’s proud heritage and national identity that includes a well-armed citizenry.

“When conflicts arise, Switzerland must put its sovereignty first,” said Blocher, a businessman and vice president of the SVP, the country's biggest party, told Reuters. “In an emergency, Switzerland should be ready to exit (the cross border agreements).”

Switzerland has one of the highest rates of private gun ownership in Europe, with nearly 48 percent of households owning a gun. In France, there are about 30 weapons per 100 people, while the figure in the Great Britain is far lower, at 6.7 guns per 100 civilians, Reuters reported citing the Australian-based think tank GunPolicy.org.

However, gun-related crime in Switzerland is low and the high number of privately owned guns harks back to a long tradition of self-defense and to the Swiss policy of near-universal conscription, Reuters reported.

In 2015, 11 percent of the 20,600 soldiers who left the Swiss Army opted to keep their assault rifles which upon departure are modified to fire single shots, according to Reuters. The number of soldiers choosing to keep their weapons has been declining for several years.

Switzerland's grassroots gun lobby ProTELL, named after the 14th-century folk hero William Tell, is prepared to call for a referendum on the EU bloc’s proposal, if necessary.

“With our direct democracy, Swiss people are accustomed to having the last word,” ProTell's Dominik Riner told Reuters. “We're opposed to any and all efforts to make current weapons laws more restrictive.”

Europe plans to finalize its gun directive later this year, Reuters reported.

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