BERLIN — The German Parliament overwhelmingly adopted a symbolic but fraught resolution on Thursday declaring the killings of Armenians by Ottoman Turks in 1915 a genocide, escalating tensions with Turkey at a diplomatically delicate juncture.

The Turkish government angrily denounced the vote as “null and void,’’ and President Recep Tayyip Erdogan called his ambassador in Germany back to Ankara for consultations.

“The way to close the dark pages of your own history is not by defaming the histories of other countries with irresponsible and baseless decisions,’’ Turkey’s foreign minister, Mevlut Cavusoglu, wrote on Twitter. In Ankara, Prime Minister Binali Yildirim said, “There is no shameful incident in our past that would make us bow our heads.’’

Germany needs Turkey’s help in following through on a deal with the European Union to manage the refugee crisis attributed in large part to the Syrian civil war. At the same time, the German chancellor, Angela Merkel, has been under pressure not to be seen as caving to pressure from Ankara to compromise on Western values, particularly after a recent dust-up over freedom of speech set off by a German comedian’s satire that outraged Erdogan.

For Turkey, there is scarcely a more delicate topic than what historians say was the murder of more than 1 million Armenians and other Christian minorities in 1915-16. In April, Erdogan visited the Armenian Patriarchate of Turkey and, in a carefully worded statement, extended condolences to the families of those who had died, but the Turkish government has long rejected the term genocide.

Ankara has noted that thousands of people, many of them Turks, died in the civil war that destroyed the Ottoman Empire and has argued that the estimates of the number of Armenian deaths have been exaggerated.

The issue is also fraught for Germany. At the time of the killings, Germany, led by Kaiser Wilhelm II, was allied with the Ottomans, fighting alongside the Austro-Hungarian Empire against Britain, France, and Russia in World War I. Acceptance of German responsibility for the atrocities of World War II has become an established part of the nation’s culture, and historians and activists have said that the Armenian resolution was an important step in acknowledging Germany’s indirect involvement in the 1915 killings.

Pope Francis called the killings a genocide last year, but the United States has long skirted the issue. President Obama stopped short of using the word — most recently in a statement marking Armenian Remembrance Day on April 24 — though he used the term before becoming president.

Merkel’s Christian Democratic Union and its coalition partners supported the resolution, which was originally proposed for last year, to mark the centennial of the start of the killings. But it was repeatedly delayed, most recently in February, over concerns about angering Ankara.

As the vote approached, debate intensified in Germany, which is home to an estimated 3 million people of Turkish descent, many with dual citizenship. About 2,000 Turks demonstrated last weekend in Berlin, saying that Parliament is not a court and therefore should not pass judgment.

Cem Ozdemir, co-chairman of the opposition Greens and a driving force behind the resolution, accused Merkel of paying little heed to Turkey for most of her decade in power, until circumstances forced her to engage with Erdogan.

On Thursday, Ozdemir said there was “never a favorable time to speak about something as dreadful as genocide.’’

Ozdemir read century-old statements by officials of the German Empire showing they knew that up to 90 percent of Armenians had been killed.

“Working through the Shoah is the basis of democracy in Germany,’’ Ozdemir said, referring to the Holocaust. “This genocide is also waiting to be worked through.’’

He noted that there were Turks who saved Armenians. “Before them, we bow down with highest respect,’’ he said.

Including Germany, 12 of the European Union’s 28 members have recognized the Armenian killings as genocide.