GENEVA - Switzerland voted Sunday to impose curbs on immigration by European Union citizens, in a nail-bitingly close referendum that threatened to ignite a row with Brussels. Final results showed that 50.3 percent of voters had backed the “Stop Mass Immigration” proposal pushed by right-wing populists, even though it could mean the demise of a raft of deals signed in 1999 with the EU including on the economic front.“This is a turning point in our immigration policy,” said Toni Brunner, head of the Swiss People’s Party (SVP), which piloted the referendum campaign in a country that has steadfastly resisted joining the EU. Switzerland’s seven-member multiparty government, the Federal Council, in which the SVP has one cabinet post, had opposed the measure on the grounds that it could hit the economy and undermine the country’s credibility as a negotiating partner.However in Switzerland, the people have the last word on a huge range of issues in referendums, and the government acknowledged that. “The Federal Council will without delay begin the work needed to implement the decision of the people,” it said in a statement. It added that it would examine over coming weeks how to “recast relations between Switzerland and the EU”, underlining that the current rules would remain in force until a new version has been drawn up.The measure binds the government to renegotiate within three years a deal with Brussels that since 2007 has given most EU citizens free access to the country’s labour market. It also means that Switzerland will add a clause to its constitution stating migration must serve the nation’s economic interests. The SVP, which is hawkish about Swiss sovereignty, claims the country has been swamped by migrants. It says that with 80,000 EU citizens arriving per year — rather than the 8,000 predicted before the rules were liberalised — it is time for the nation of eight million people to rein things in.Proponents argued that EU citizens undercut Swiss workers, and that overpopulation has driven up rents, stretched the health and education systems, overloaded the road and rail networks, and eaten into the landscape due to housing construction. In a nod towards such concerns, the government recently adopted measures making it harder for newly-arrived EU citizens to apply for Swiss social security. The measure will mean a return to the annual sector-by-sector limits on work permits for foreigners in force in the past.It leaves it up to the authorities to set the numbers. Opponents, also including lobby groups from across the economy, have said it would be foolhardy to revive the bureaucratic hurdles of the past. They say restricting the hiring of EU citizens would act as a brake on the wealthy Swiss economy, which enjoys virtually full employment but has an ageing population, and could also hurt trade with a disgruntled EU.Brussels warns that Switzerland cannot pick and choose from the binding package of deals negotiated painstakingly in the 1990s, seen as a way for the country to enjoy the benefits of access to the EU market without membership. But the vote has also been watched closely by eurosceptics within the EU who want to rein in immigration among its member states, notably from eastern to western Europe.“A signal from Switzerland is clearly going to be welcome,” SVP politician Oskar Freysinger told public broadcaster RTS. Switzerland is ringed by EU member countries and does the bulk of its trade with the bloc. The labour market accord is part of a raft of deals signed with the EU in 1999 after five years of talks, approved by Swiss voters in 2000 and phased in. Critics of the migration control plan underline that the treaty with the EU already allowed Switzerland to reimpose temporary quotas — something it has deployed to control numbers of workers from the EU’s ex-communist member states.But the quota clause expires this year. Immigration and national identity are traditional political themes in a country with a long history of drawing foreign workers and some of Europe’s toughest rules for obtaining citizenship. But over recent years, the proportion of foreigners has risen from around one-fifth of the population to roughly a quarter. The majority of recent immigrants are from neighbouring Germany, Italy and France, as well as Portugal. There was a clear division in the vote, with Switzerland’s German- and Italian-speaking cantons, in favour, and French-speaking regions voting against.The European Commission said it would assess EU ties with Switzerland after the Alpine country voted Sunday to limit immigration from the European Union, its biggest trading partner by far.“The EU will examine the implications of this initiative on EU-Swiss relations as a whole,” said a statement after Swiss results showed a narrow victory for a proposal pushed by right-wing populists. The European Commission said it “regrets” the Swiss vote, which “goes against the principle of free movement of persons between the EU and Switzerland.” Although Switzerland is not an EU member, it signed onto the EU accord for free movement of citizens in 1999 and implemented it from 2002. While Sunday’s vote focused only on that issue, fall-out from the result could imperil Switzerland’s trade with the big European bloc, which its economy depends on. Brussels has already made it clear that Bern cannot cherry-pick among EU advantages. An estimated 400,000 Swiss citizens live in the EU, many of them dual nationals, while more than a million EU citizens currently live in Switzerland.