BERLIN (Reuters) - A proposal to give religion lessons the same status as ethics classes in Berlin schools was defeated in a referendum on Sunday, having sparked a debate across Germany on tolerance and the integration of Muslims.

Secular ethics has been a compulsory topic in Berlin since 2006 after the “honor killing” of a Turkish woman who was murdered by her brother because of her western lifestyle. Religion, compulsory in most other German states, is only optional in the capital.

Advocates wanted to change the rules so that pupils could choose between ethics and religion -- with Muslims, Catholics and Protestants taught separately.

But only about 14.1 percent of total eligible voters in Berlin cast their ballots in favor of the ‘Pro Reli’ proposal, election officials said.

That fell far short of the 25 percent “yes” votes needed -- or a total of 611,422 -- among 2.45 million eligible voters. Official data showed 51.5 percent opposed the proposal and 48.4 percent backed it. Voter turnout was 29 percent.

The referendum aroused strong feelings in Berlin. Ethics campaigners said faith-based religion lessons risked opening divisions and setting a predominantly Christian agenda.

“This shows that those in ‘Pro Reli’ who were portraying this as a ‘freedom’ issue -- as if the Russians were about to invade -- are out of touch with the real situation in Berlin,” said Mayor Klaus Wowereit, a fierce opponent of the measure.

Christoph Lehmann, who had led the ‘Pro Reli’ campaign that enlisted celebrities from around Germany as well as conservative Chancellor Angela Merkel, said he was disappointed with the vote but pleased with the referendum’s impact.

“It was a valuable discussion,” he told ARD television. “For months Berlin, which many always thought of as an ‘atheist’ city, was discussing religion.”

After World War Two, authorities tried to use churches to strengthen values in a people shaken by the horrors of war and the Holocaust.

While Germany has roughly equal numbers of Catholics and Protestants, Berlin has a long secular tradition. It is also home to Germany’s biggest Muslim, mainly Turkish, community of about 220,000 people.