Russia said on Saturday it will step up air strikes in Syria, escalating a military intervention which Moscow says is weakening Islamic State militants but which Western powers say aims to support President Bashar al-Assad.<br />A senior Russian military officer said Russian jets based in western Syria had carried out more than 60 sorties in 72 hours across Syria.<br />"We will not only continue strikes... We will also increase their intensity," said Andrei Kartapolov from the Russian army General Staff.<br />Russia's air campaign in Syria, where a U.S.-led air coalition and fighters on the ground from regional states are already entangled in a four-year-old civil war, has drawn strong criticism from the United States and its allies.<br />President Barack Obama, wary of military commitments in the Middle East after America's costly war in Iraq, warned President Vladimir Putin he was defending a crumbling authoritarian ally and could be sucked into a "quagmire".
