Grand Mufti Shawki Allam, the Egyptian state’s authority responsible for issuing religious edicts, said on Monday in a statement that Islamic State (IS) executing 21 Egyptian Copts in Libya was an act empty of the “great tolerance of Islam”.

He insisted that the militant group has no understanding of the meaning of the Holy Quran.

He added that the IS group's attribution of certain sayings to Prophet Mohamed was erroneous.

IS published a video on Sunday in which it justified its beheading of 21 Egyptian Coptic Christians in Libya by quoting alleged sayings by the prophet.  

In his statement, Allam mourned the victims.

He said that extremist groups are attempting to spread “sectarian strife and infighting between Muslims and their Christian brethren”.

He however added that he has faith that Egypt will be victorious against its enemies.

“The blood of our Christian children and brothers is the same blood as that of Muslims... which belongs to the Egyptian nation,” he said.

Egypt's only comfort is that its beloved children died on the side of Right in a battle againt Wrong, Allam said.

The United Arab Emirates-based Council of Religious Elders, chaired by the Grand Imam of Egypt's Al-Azhar, Ahmed El-Tayeb, condemned the killings, declaring them to be entirely against the teachings of Islam, and extended condolences to Egyptians, Egypt’s Orthodox Pope Tawadros II and the families of the victims.

The council urged for unity in facing “malevolent terrorism that claims innocent lives.”

Egypt's army conducted airstrikes against IS locations in coordination with the Libyan army early on Monday, according to the Libyan army. The Egyptian army has released footage of its operations. 

Egypt’s presidency is preparing plans to evacuate Egyptians wanting to flee Libya.

Egypt is battling militant group Ansar Bayt Al-Maqdis in the governorate of North Sinai. In late 2014, the group swore allegiance to IS, which first made its appearance in Syria and now controls large swathes of both Syria and Iraq.