Afghan Taliban, the Islamist militant group which has been waging a deadly armed insurgency in Afghanistan, has condemned Islamic State (Isis) for the brutality shown in the latest execution video.

The Taliban, which itself is often accused of savage methods against the Afghan government, said the killing of prisoners by IS was not in keeping with the principles of Islam.

"A horrific video was released yesterday (11 August) showing kidnappers who associate themselves with Daesh (IS) brutally martyring several white-bearded tribal elders and villagers with explosives," the Afghan group said.

IS jihadists recently released a video showing a new method of execution by planting explosives among a group of men. In the footage, IS militants are seen burying several explosives before leading a group of men towards the bombs. The video was reportedly shot in the eastern Afghan province of Nangarhar.

Taliban said: "This offence and other such brutal actions by a few irresponsible ignorant individuals under the guise of Islam and Muslims are intolerable."

The rivalry between Afghan Taliban and IS has intensified in recent months with the latter making serious inroads into the war-torn country.

Ever since the Iraqi Sunni insurgent organisation attempted to wade into the ongoing Afghan insurgency capitalising on the infighting in Taliban, the Afghan group has been sending strong warning signals.

Clashes have also been reported between Taliban fighters and supporters of IS in Afghanistan in recent weeks.