Up to 35,000 Syrians have massed on the Turkish border, which has been closed for three days, authorities say, and a possible siege of the major city of Aleppo could send thousands more in the coming days.
Several other Sunni Muslim states, including Saudi Arabia, say they are ready to participate in ground operations against the IS, but the UAE's foreign minister says American leadership "is a pre-requisite."
Afghanistan, Pakistan, the US and China concluded their talks aimed at ending Afghanistan's 15-year Saturday with a call for direct negotiations between the government and the Taliban by the end of February.
The gunmen responsible for the deadly attack on Pakistan's Bacha Khan University were trained in Afghanistan and the assault was controlled by a Pakistani Taliban militant from somewhere in Afghanistan.
The Islamic State on Tuesday acknowledged the death of the militant known as 'Jihadi John' – identified by the US military as Kuwaiti-born British citizen Mohammed Emwazi – in its English-language magazine Dabiq.