German Chancellor Angela Merkel said at the weekend that Germany's attempts to build a multicultural society had "utterly failed."

Merkel's remarks, made at a meeting of young members of her center-right Christian Democratic Union, has triggered a public debate over how to deal with millions of immigrants who arrived in Germany during the country's postwar economic boom in the 1960s to make their fortunes.

Merkel said immigrants are welcome in Germany, but they must learn the country's language and accept the country's cultural norms.

She said the concept of multiculturalism, long championed by the German left, had been discredited. "This multicultural approach, saying that we simply live side by side and live happily with each other has failed, utterly failed."

Germany is one of some European countries that have been skeptical of the idea of building a multicultural society in their countries after millions of foreign laborers came in droves during the postwar economic booms in the mid-20th century.