He regularly tweeted the Afghan government’s position and had more than 142,000 followers on Twitter.
The killing comes days after the Taliban assaulted the defence minister’s home in Kabul.
“Unfortunately, the savage terrorists have committed a cowardly act once again and martyred a patriotic Afghan,” interior ministry spokesman Mirwais Stanikzai said.
Taliban militants have captured large swathes of the countryside and are now attacking key cities including Kandahar in the south, economically important Herat, and Lashkar Gar – capital of Helmand Province.
It comes after US and other international forces announced their withdrawal following two decades of operations.
Diplomats said Afghan government officials requested the meeting in view of the growing unrest. It is set to start at 10:00 local time (14:00 GMT) in New York, diplomats said.
Neighbouring nations are also set to discuss the situation in Afghanistan on Friday.
Turkmen President Gurbanguly Berdymukhamedov called Afghanistan “the question that worries us all” on Wednesday during a state television broadcast, AFP news agency reports.
On Thursday the European Union called for “an urgent, comprehensive and permanent ceasefire” in Afghanistan as the “senseless violence” escalates.