Voters in Switzerland appeared on Sunday to have rejected an unprecedented far-right proposal to cap the country’s population at 10 million in a divisive referendum dubbed “the Swiss Brexit”.

A projection by ⁠the national broadcaster SRF, which traditionally calls ​referendum votes, showed that about 55% of voters were against the proposal by the Swiss People’s party (SVP) and about 45% were in favour.

A different outcome would have obliged the Swiss government to limit the population, currently 9.1 million, to 10 million by 2050, enacting tough restrictions on family reunification, residency permits and asylum if the number had reached 9.5 million before that date.

Under the proposals, if the threshold of 10 million people was exceeded before 2050, the Swiss government would have been obliged to withdraw from the country’s free movement agreement with the EU – ending its access to the bloc’s single market.

The SVP, which has the most seats in parliament, has for years fuelled anti-immigrant sentiment, especially concerning workers from neighbouring EU countries.

The party had insisted that a so-called “sustainability initiative” was needed to address the increase in population, which it argued was putting pressure on Swiss infrastructure, housing, social programmes, natural resources and way of life.

Switzerland’s population has grown far faster than that of surrounding EU states, rising by 23% since the free movement agreement came into effect in 2002. Economic output has risen by about 24% over the same period, government figures show. About 27% of Swiss residents are not citizens, according to official data.

Urs Bieri, from the polling firm GFS Bern, told Reuters that the initiative failed to pass because people were unconvinced by the plan and worried about the possible side-effects despite widespread concern about population growth.

“Voters were worried ‌about negative consequences for Switzerland’s relationship with the EU and for the labour market,” he said. “People are also worried about things like having enough care and ‌health workers. Also, there’s a feeling that in the current international environment it’s not sensible for a small country to do this.”

The seven-member government, made up of ministers from Switzerland’s four biggest parties, including the SVP, was collectively against the initiative, warning it would threaten national stability, harm the economy and hurt Swiss prosperity.

Business groups were also concerned that a population cap would have limited access to foreign workers while damaging the economy and relations with Brussels.

Polls had forecast a close outcome. The projection tallied with a final survey by GFS Bern, which had predicted the proposal would be narrowly rejected.

Switzerland’s system of direct democracy allows for “popular initiatives” that are put to a referendum if they get 100,000 backers within 18 months. Typically held four times a year, plebiscites are a long-favoured tool of the anti-immigration SVP.

While many countries have limits on immigration, none has ever voted to limit its population.