In a fatwa posted online, also endorsed by a US imam from Texas, the 38 scholars argue that "any attack on Canada will be an attack on the freedom of Canadian Muslims."

They also forbid Muslims from joining or encouraging others to join IS, saying anyone who helps Muslim youths in particular "to travel secretly or without the consent of parents to join IS... will face the wrath of Allah in this world and in the next world."

The fatwa was penned by Imam Syed Soharwardy, head of the Islamic Supreme Council of Canada in Calgary, and signed by others from across Canada.

In it, Soharwardy condemns Canadian, US and other Western nations' policies in the Middle East as "unjust" and "based upon Islamophobia, bias and intolerance towards Muslims."

But he also urges young Muslims not to be taken in by the IS group, which he says has fostered anti-Western sentiments for its own gain, and has violated Islamic tenets "in the most horrific and inhumane way."

"The behavior and the actions of ISIS/ISIL has consistently proven that they are NOT Muslims and they cannot be trusted by the Muslims," he said.

"Their struggle cannot be an Islamic struggle and their war cannot be called 'Jihad'. Rather, it is pure terrorism and HARAAM (forbidden)."