Meeting in Stuttgart, the annual conference of the Christian Democratic Union (CDU) voted for a resolution calling for a new sentence to be added to the constitution: "The language of the Federal Republic shall be German."

While party conference resolutions are not binding on party leaders, they do demonstrate political priorities.

Observers said the move was likely to be seen as a show of sympathy not just for school teachers who complain that almost nobody speaks grammatically pure German nowadays, but also for right-wingers who fear foreigners are taking over.

Merkel, who faces a close general election next year and has rebuffed calls for everything from "the family" to sport and high culture to be made constitutionally sacred, opposed the resolution.

"I don't think it's good to put every last thing into the constitution," she told RTL television news.

On the margins of the conference, delegates denied that the move marked a resurgence of nationalism.

Most said they just wanted Germans to become as proud of German as the French are of French and the Poles are of Polish.

"Language is the most precious jewel of culture. Why shouldn't we protect it in the constitution?" said Otto Wulff, who heads the CDU's national committee of retirees.

Maria Boehmer, Merkel's aide for liaison with ethnic minorities, also denied the vote was hostile to anyone.

Pressure to assimilate?

An organization of secular Turks was not so sure. Kenan Kolat, chairman of the Turkish Community Association, said, "CDU politicians are pandering to latent fear of migrants.

"We interpret this idea as pressure to assimilate. It does not conform to democratic practice. That's how migrant communities will perceive it."

About 100 million people speak German. In Austria, the language is prescribed in the constitution as official. Germany has two very small ethnic minorities with their own official languages, Sorbian and Danish.

Kolat said he did not see what ill the CDU was trying to correct, since only German can be used in government.

Some in the Social Democratic Party (SPD), which is in coalition with the CDU in the federal government, poured scorn on the CDU idea. SPD education spokesman Joerg Tauss called it "utter nonsense."

How about Turkish?

The debate about whether German is under threat was revived recently when the new co-leader of the Greens, Cem Oezdemir, called for optional Turkish-language courses in public schools.

Conservatives were outraged, and retorted that migrant children could not even speak German. Ozdemir is of Turkish extraction but was born and bred in Germany.

A group that believes well-spoken German is under threat, the German Language Society VDS, welcomed the resolution.

VDS Secretary Holger Klatte said, "We hope German will be better taught in the schools."