Erdogan called the events of World War I "our shared pain" and acknowledged that the deportation of Armenians in 1915 had "inhumane consequences."
Erdogan released a statement in Turkish, Armenian and seven other languages, expressing hope that those killed are in peace and offering Turkey's condolences to their descendants. The message came a day before Armenians mark the 99th anniversary of the killings in 1915 by Ottoman Turks.
The episode is considered by many historians as the first genocide of the 20th century. They estimate that about 1.5 million Armenians died. Turkey rejects the term genocide. It says the figures are inflated and that there were deaths on both sides as the Ottoman Empire collapsed.
Erdogan, in his message, admitted that the deportations had dire consequences, but did not use the term "genocide." He said millions of people "of all religions and ethnicities" lost their lives during the war.
"The incidents of the First World War are our shared pain," Erdogan's message read.
Erdogan said the events should not prevent "Turks and Armenians from establishing compassion and mutually humane attitudes toward one another" and asked that they not be used against Turkey.
"Using the events of 1915 as an excuse for hostility against Turkey and turning this issue into a matter of political conflict is inadmissible," Erdogan said.
Erdogan also renewed a Turkish proposal for a joint study of the events, involving scholars from both sides.