President Vladimir V. Putin of Russia told the Azerbaijani leader, Ilham Aliyev, in a phone call, “that the tragic incident took place in Russian airspace.”

Russian President Vladimir Putin apologized for the plane crash in Russian air space on Christmas Day that left 38 people dead in a statement that said Russia was targeting Ukrainian drones over the plane’s planned destination at the time, but stopped short of taking responsibility.

Putin’s apology came as allegations mounted that the plane had been shot down by Russian air defenses attempting to deflect a Ukrainian drone strike near Grozny, the regional capital of the Russian republic of Chechnya.