BERLIN (Reuters) – The German parliament overwhelmingly approved on Friday a resolution branding the mass killings of up to 1.5 million Armenians by Ottoman Turkish forces a century ago as genocide.

The vote marks a significant change of stance for Germany, Turkey’s biggest trade partner in the European Union and home to a large ethnic Turkish diaspora. Unlike France and some two dozen other countries, Berlin has long resisted using the word. The term ‘genocide’ also has special resonance in Germany, which has worked hard to come to terms with its responsibility for the murder of six million Jews in the Holocaust.

In a parliamentary session to commemorate the 100th anniversary of the start of the killings, all parliamentary groups in the Bundestag lower house backed the resolution in a vote likely to infuriate Turkish President Tayyip Erdogan.

“What happened in the middle of the First World War in the Ottoman Empire under the eyes of the world was a genocide,” Bundestag President Norbert Lammert said at the start of German lawmakers’ debate on the resolution.

German President Joachim Gauck also used the word ‘genocide’ in a speech on Thursday. Gauck, a former East German pastor with a penchant for defying convention, also suggested Germany itself might bear some of the blame because of its actions during World War One.