Moderate Muslim leaders delivered a ringing denunciation of the Islamic State (ISIS), warning members of their community in France that joining the jihadist group will only "drag you to your death, to hellfire, because suicide and slaughter are not permitted in Islam."

The Muslim community leaders made their statements on Monday as they trooped to a makeshift memorial to pay their respects to the slain victims of Friday's terror attacks in Paris, CNN reported.

Several of the terrorists who blew themselves up were believed to be French nationals who traveled to Syria to join ISIS.

Based from information shared by the French interior ministry, French nationals comprise the biggest number of European jihadis in Iraq and Syria with at least 570 of them fighting for ISIS.

Abdalali Mamoun, an imam at a southern Paris mosque, was one of 20 Muslim clerics who came to lay flowers near the Bataclan theatre where four terrorists wearing explosive vests killed more than 80 people during a rock concert.

The imam urged young French Muslims to stay away from ISIS.

"You're mistaken in supporting that movement, ISIS. It will drag you to your death, to hellfire, because suicide and slaughter are not permitted in Islam," he said.

Another imam noted that the victims were killed indiscriminately.

"As French citizens, and as human beings, we have been wounded by this attack," Yasser Laouti, spokesman for the Collective Against Islamophobia in France, said. "They killed Christians, Muslims and Jews indiscriminately."

However, the French Muslim leaders said that although they sympathise with the families of the terror attack victims, they do not support the French airstrikes in the ISIS capital of Raqqa, in Syria.

"I saw that yesterday, after what happened, (French President) Francois Hollande decided to bomb Raqqa," human rights activist Samia Hathroubi said. "Do we really think that bombing a city of 200,000 people will help us combat terrorism in our own country?"

The French Muslim leaders blamed discrimination and poverty, political and economic marginalisation as some of the reasons why so many young French Muslims are joining ISIS.

Earlier, Muslim leaders throughout the world strongly condemned the terrorist attacks in Paris, the International Business Times reported.

Iranian President Hassan Rouhani sent a message of condolences to Hollande on Saturday, informing him Iran was offering its thoughts and prayers to the French people. Iran and its allies, Hezbollah and the government of Syrian President Bashar al-Assad, have been fighting ISIS.

Indonesian President Joko "Jokowi" Widodo also condemned the violence that took place in Paris, as he called for international cooperation against terrorism, according to the Jakarta Post. Indonesia is the largest Muslim country in the world.

The leaders of Saudi Arabia, the United Arab Emirates, Kuwait, Qatar and Egypt also denounced the attacks just hours after the attacks late Friday.

The Council on American-Islamic Relations, the largest Muslim civil rights and advocacy organisation in the United States, also joined in the condemnation, saying: "These savage and despicable attacks on civilians, whether they occur in Paris, Beirut or any other city, are outrageous and without justification."

In YouTube video that became viral, one Moroccan Muslim named Wafi Abdouss blasted the ISIS terrorists, saying "these so-called jihadists only represent themselves."