Russia and the United States clashed at the United Nations on Tuesday, accusing each other of supporting terrorism during a Security Council meeting convened over a sudden escalation of fighting in Syria.

Russia said on Wednesday that it strongly backs the actions of the Syrian leadership to counter an offensive by what it said were terrorist groups receiving support, including drones and training, from outside the country.

Images shared on social media have illustrated the anger that Syrian rebels fighting President Bashar al-Assad feel toward his ally Vladimir Putin. The Russian leader has been indispensable in propping up Assad's regime during the brutal Syrian civil war that started in 2011 but has been essentially frozen over the last four years.