The Swiss government's decision to ban the building of minarets was the result of a "populist political campaign of religious intolerance" led by a far-right party, the Anti-Defamation League charged on Wednesday.

The ADL, which noted that the Federation of Swiss Jewish Communities opposed the measure, called on Bern "to be vigilant in its commitment to ensuring freedom of religion."

The UN human rights chief says Switzerland's minaret ban is discriminatory and puts it on a collision course with international law.

Navi Pillay stopped short of declaring the Alpine country's ban on the Islamic towers illegal.

But she condemned Tuesday the "anti-foreigner scare-mongering" that produced the vote, and its "deeply divisive" result.

The referendum backed by nationalist parties was approved by 57.5 percent of the Swiss population Sunday. It does not affect the country's four existing minarets.

Europe's top human rights watchdog said Monday that the ban could violate fundamental liberties, and questioned whether human rights ought to be subject to popular votes.