Although it has lost land in both Syria and Iraq, ISIS still holds large parts of the two countries of Iraq and Syria where as many 10 million people live under their control, according to Daily Mail.
There have been reports that Al-Qaeda commanders have been sent to north-west Syria to begin their operation.
Saif al-Adel, a veteran Egyptian terrorist, seen as his deputy and operational field commander, is one of the men who has been sent.
Al-Qaeda has been concerned Jabhat al-Nusra could be persuaded by Persian Gulf states like Qatar to sever ties with them and disband in return for aid.
Zawahiri said he was ‘proud’ of Jabhat al-Nusra (Nusra Front) and its link to al-Qaeda in the video.
According to the Daily Telegraph, he said: ‘If they create their government, and choose their emir, what they choose is our choice.’
He criticised ISIS and compared them to a centuries old Islamic group, Khawarij, which was brutal against fellow Muslims.
‘The Islamic nation in Greater Syria has backed [al-Nusra], realizing the difference between the correctness of its methods and the methods of the new Khawarij,’ he said.