The Taliban last week announced its interim government which was made up entirely of men, most of them ethnic Pashtuns, and dominated by veteran members of the Islamist fundamentalist movement.
Iran, which shares a more than 900 kilometre (550 mile) border with Afghanistan, already hosts nearly 3.5 million Afghans and fears a new influx of refugees.
Iran has had a contentious relationship with the Taliban during their 1996-2001 rule of an Islamic Emirate of Afghanistan, which it has never recognised.
Tehran had nevertheless seemed to be moving towards a rapprochement with the Taliban in recent months.
However, on 6 September, Tehran "strongly" condemned the Taliban's assault on Afghanistan's Panjshir Valley, the last stronghold of resistance to the movement, which claimed to have taken complete control of the area.