Merkel and her conservative allies have long argued that immigrant groups must fully adapt to the German way of life, including abandoning aspects of their native cultures.

Turkish communities
 
About 2.5 million people of Turkish origin live in Germany, more than in any other country in western Europe.

While some are well integrated into German life, others live in separate urban communities, speak only Turkish, and stick to old traditions.

"A lot of Turks finally got the feeling a government leader was listening to them. That's something Merkel could do too"

Ali Kizilkaya,
head of Islamrat
Ali Kizilkaya, head of the German Muslim group Islamrat, told the Tagesspiegel daily newspaper that Erdogan had touched many Turks in Germany by encouraging them not to forget their culture and expressed disbelief at the outrage over his comments.

"A lot of Turks finally got the feeling a government leader was listening to them. That's something Merkel could do too," Kizilkaya said of Erdogan's visit.

Merkel, who opposes Turkey's bid to join the European Union, has made improving integration a priority of her government, appointing a co-ordinator for the issue and holding regular "summits" with leading immigrant groups.

But both she and her party have tended to put the onus on immigrants to adapt.

When asked last month why the government's "integration plan" existed only in German, she replied that German was the national language and those who could not read it should learn.

Fire victims buried

Senior conservatives, including Wolfgang Schauble, Merkel's interior minister, were quick to reject a suggestion by Erdogan during his visit that Turkish-language schools and universities should be set up in Germany.

Tensions between Germans and Turks were highlighted before Erdogan's trip by a fire in a housing block in the western city of Ludwigshafen which killed nine people with Turkish roots on February 3.

The cause of the blaze is unknown but the local Turkish community and Turkish media have speculated that it was racially motivated.

Erdogan visited the site on Thursday and the victims were buried in Turkey on Monday.