The White House signaled Thursday that President Barack Obama won’t use the word “genocide” to describe the killing of 1.5 million Armenians at the hands of Ottoman Empire — continuing to break a longstanding pledge.

As a candidate for office, Mr. Obama said he would use the word “genocide” to describe the killings. In a strongly worded statement in 2008, Mr. Obama said: “The Armenian Genocide is not an allegation, a personal opinion, or a point of view, but rather a widely documented fact supported by an overwhelming body of historical evidence.