Vodafone is seeking to cut around 600 jobs in Germany, representing 5.7 percent of its workforce there, as it grapples with harsh competition and lower revenues, its German division said on Tuesday.
"We have started voluntary job cuts. Nobody is forced to accept the offer," a company spokesmand said.
Vodafone Germany last month announced it would seek to cut 100 million euros in annual costs, saying it would try to avoid forced redundancies.
Vodafone and rivals Deutsche Telekom, Telefonica Deutschland and KPN's E-Plus are in a fierce battle for German customers, who are catching up with the rest of Europe in switching to smartphones from basic mobiles.
In addition, mobile carriers are suffering from stricter regulation.
The cutbacks come on top of a two-year restructuring programme launched by Vodafone Germany in April last year, affecting 500 jobs.