Threatening to jeopardize “all diplomatic, economic, trade, political, military and Nato relations” with Germany, Turkey’s president Recep Tayyip Erdogan bluntly warned German lawmakers to avoid a vote calling the early 20th century massacres of Armenians a genocide.

The German parliament, called the Bundestag, is set to vote on official recognition on June 2. The resolution is entitled “Remembrance and commemoration of the genocide of Armenians and other Christian minorities in 1915 and 1916” also carries the contested word “genocide” throughout the text.

The vote comes just over a year after President Joachim Gauck became Germany’s highest ranking official to describe the massacre as a “genocide”, drawing a fierce response from Turkey.

The resolution, which has been in preparation since last year, refers to the atrocities against the Armenians, Greeks and other Christian minorities, clearly, saying: “Their fate exemplifies the mass exterminations, the ethnic cleansing, the expulsions and indeed the genocides that marked the 20th century in such a terrible way.”

It also states that the “German Empire bears partial responsibility for the events.”

Germany was allied with the Ottomans at the time and historians agree that German military officers and officials were aware of the killings, reported on the massacres to Berlin, and in some cases were involved in decisions that led to the deaths of Christians.

Turkey’s deputy prime minister and government spokesman Numan Kurtulmus also added a warning, stating that “Germany must be careful concerning its relations with Turkey.”

“I do not think that the German parliament will destroy this relationship for the sake of two or three politicians” who had put the resolution before the Bundestag, he added.