ISIS leader Abu Bakr Al Baghdadi called for attacks in the West in a purported new audio recording released via Telegram on the Eid Al Adha holiday.
It is the first apparent recording of the leader to be released since September last year and comes in the wake of major territorial losses for the group in Iraq and Syria.
"Those who forget their religion, patience, jihad against their enemies, and their certainty in the creator's promise lose and are disgraced," the leader said. "But when they hold on to it, they are mighty and victorious, even if after a certain time."
The term jihad, an internal spiritual struggle or a fight for a morally better society, has been used repeatedly by ISIS and other terror groups to justify violence.
ISIS overran large swathes of Syria and neighbouring Iraq in 2014, proclaiming a "caliphate" in areas they controlled.
They have since lost most of that to various offensives in both countries.
The "caliphate will remain, God willing", Al Baghdadi said in Wednesday's recording, addressing followers in the Middle East, Asia and Africa.
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It was not clear when the message was recorded, but the leader appeared to criticise a $100-million (Dh367.3 million) pledge by Saudi Arabia last week to help rebuild Syria's northeast.
He threatened the United States and Russia, who have both backed offensives against ISIS in Iraq and Syria, saying that his fighters had prepared "horrors" for them.
Al Baghdadi also criticised Syria's rebel fighters for agreeing to surrender deals with the Damascus regime, and called on opposition fighters to join his group.
The leader has been pronounced dead on several occasions, but an Iraqi intelligence official said in May that he remains alive in Syrian territory by the Iraqi border where recent isolated attacks by ISIS recently took place. Al Baghdadi is said to move around with only a small group of followers to avoid surveillance.
One day after the release of the audio a knife attack that left two people dead and one seriously injured in a Paris suburb was claimed by ISIS.
The attacker, who has not yet been identified, was shot and killed by police when he ignored their warnings.
Despite ISIS taking responsibility for the deadly attack, an official from the Paris prosecutor's office, the office responsible for investigating acts of terror, told The National the stabbing was not motivated by terrorism.
She explained that since the incident was not terror related it was being dealt with locally by the Versailles police. However the man had been on a terror watch list after expressing extremist views, Agence France-Presse reported. And the town of Trappes has previously been associated with radicalisation and is thought to be a source of ISIS foreign fighters.
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Originally from Iraq, Al Baghdadi has been dubbed the "most wanted man on the planet" and the United States is offering a $25 million reward for his capture.
Also on Wednesday ISIS' media arm released a video of four boys it said were behind multiple attacks on police targets in the Russian region of Chechnya two days ago which were claimed by the group.
Three of them brandished big knives and the youngest held up a phone with an ISIS flag displayed on the screen as they pledged allegiance in Russian to Al Baghdadi.
Though the authenticity of the video and identities of the individuals have not been verified, the ages of the boys matched the statements by local officials who said the attackers were minors, one as young as 11.
In the attacks on Monday, which included a botched suicide bombing and a knife attack on a police station, four of the assailants were shot dead. The fifth was hospitalised after he blew himself up but survived, Russian news agencies and officials said.
The young boys described themselves as fighters and threatened to attack "infidels".
The mainly Muslim internal republic of Chechnya has been dogged by attacks and a simmering insurgency since Moscow fought two wars with separatists there following the 1991 breakup of the Soviet Union.