Switzerland's biggest Jewish groups said Wednesday that a far-right push to ban the construction of minarets here was a 'threat' to religious harmony and hindered the integration of Muslims. 'The referendum infringes religious freedom, a concept enshrined in the constitution,' said the Swiss Federation of Jewish Communities and the Platform of Liberal Jews in Switzerland in a statement. It 'also poses a threat to peaceful relations between the religions and inhibits the integration endeavours of Muslims in Switzerland,' they added. Swiss voters are to decide during a referendum on November 29 whether to ban the construction of minarets in Switzerland, a proposal launched by right-wing groups and backed by the country's biggest political party, the hard right Swiss People's Party (SVP). The two Jewish groups said they 'take seriously the fears of the population that extremist ideas could be disseminated in Switzerland.' 'But banning minarets is no solution -- it only creates in Muslims in Switzerland a sense of alienation and discrimination,' they said. The Swiss government and all the other major political parties are recommending a 'no' vote. In a historic move, local Christian, Jewish and Muslim leaders have also joined forces to reject a ban on minarets. In September, the Roman Catholic community joined in the call urging voters to reject the ban. Islam is the second largest religion in Switzerland after Christianity with 310,000 followers out of a population of 7.5 million. Four minarets have been built and the construction of a fifth is planned. 