President Obama blamed Russian President Vladimir Putin’s government for the “horrific violations of international law” taking place in Aleppo, and said Russia obstructed the United Nations while backing Syrian dictator Bashar Assad.

“We have seen a deliberate strategy of surrounding, besieging and starving innocent civilians,” Obama said during his final year-end press conference from the White House. “Responsibility for this brutality lies in one place alone: the Assad regime and its allies, Russia and Iran, and this blood and these atrocities are on their hands.”