The German government blocked legislation on Wednesday that could have granted dual citizenship to hundreds of thousands of immigrants even though it is trying to recruit skilled foreigners to alleviate a labor shortage.
The left-wing opposition accused Chancellor Angela Merkel's coalition of holding an antiquated world view and anti-Turkish sentiment verging on racism, setting up immigration as a campaign issue before a federal election in September.
The bills would have had most effect on German residents of Turkish origin.
"Merkel has said she wants a welcoming culture, and yet the current law on nationality doesn't foster integration but rather forces people to give up their heritage," said Thomas Oppermann, parliamentary floor leader of the Social Democrats.
"We need to change this. Germany needs immigrants."
But lawmakers from Merkel's conservatives told parliament that lowering the hurdles for immigrants to work in Germany and integrate efficiently was the key. Giving them dual citizenship which risked creating parallel societies and giving Turkey undue political leverage over Germany.
"For us, an expression of successful integration means that a person decides for Germany," senior Conservative Ole Schroeder told the Bundestag lower house of parliament. "Social diversity is not dependent on people having several nationalities."
TURKISH OR GERMAN - NOT BOTH
Germany does not allow anyone to hold two citizenships permanently although there are exceptions, such as for citizens from other European Union countries and Switzerland.
Children of migrants who are born in Germany are allowed to keep both their German nationality and that of their parents until they turn 18, when they have to choose between the two.
"Dual citizenship is granted twice as often for those without Turkish roots as for those with," said Sevim Dagdelen, daughter of Turkish migrants and an MP of the Left party.
Turkish Prime Minister Tayyip Erdogan has criticized Germany's immigration policy, saying it forced immigrants to suppress their culture and language.
One of the immigration requirements he has taken issue with is that which stipulates people joining their spouses in Germany should already have some knowledge of German. Merkel's coalition on Wednesday shot down a separate proposal from the Linke party to scrap this requirement.
Immigration leapt to the forefront of German political debate in 2010 when central banker Thilo Sarrazin published a bestselling book that argued that German culture was at risk from Muslims, who he said were a drain on state coffers.
The debate left raw nerves on both sides as German politicians initially closed ranks to condemn Sarrazin's theories, but later shifted their tone rightwards as polls showed he enjoyed widespread support. Sarrazin stepped down yet Merkel went on to declare multiculturalism had failed.
The chancellor's rhetoric has become more positive towards foreigners in recent months, although more so towards skilled laborers from abroad than those foreigners already living in Germany and struggling to integrate.