MONTREAL (CBC) - A group of Canadian and U.S. Islamic leaders on Friday issued a fatwa, or religious edict, declaring that an attack by extremists on the two countries would constitute an attack on the 10 million Muslims living in North America.

The 20 imams associated with the Islamic Supreme Council of Canada said this marked the first fatwa by the Muslim clergy declaring attacks on Canada and the U.S. to be attacks on Muslims.

"In our view, these attacks are evil, and Islam requires Muslims to stand up against this evil," the imams said in their fatwa.

Calgary Imam Syed Soharwardy, founder of the Islamic Supreme Council of Canada, said attacks on Canadian or U.S. soil are essentially attacks on Muslims.

"We are part of this society," he said. "This is my home, and if anybody attacks on Canada, in fact, attacks on my home."

The imams said it is a duty of every Muslim in Canada and the U.S. to safeguard the two countries.

"They must expose any person, Muslim or non-Muslim, who would cause harm to fellow Canadians or Americans," they said.

"It is religious obligation upon Muslims, based upon the Qur'anic teachings, that we have to be loyal to the country where we live," said Soharwardy. "We have no problems in Canada; we can practise our religion freely."

In Montreal, one of the signatories of the edict, Imam Nasir Qadri of the Anwar Musallah Mosque, said he spoke to his followers at his mosque about the issue Friday.

Most of them call Canada home and feel personally threatened by the attempted attacks, he said.

The 20 imams who signed the fatwa come from British Columbia, Alberta, Ontario, Quebec and Houston.

The fatwa comes just weeks after an attempted bombing on Christmas Day of a U.S. jet bound for Detroit from Amsterdam.

Umar Farouk Abdulmutallab, a 23-year-old Nigerian man, has been indicted on six charges, which include attempted use of a weapon of mass destruction and attempted murder.