CAIRO (Reuters) – Muslim groups and individuals  should not use weapons of mass destruction against non-Muslim  countries partly because any attack could also kill Muslims,  Egypt’s state-appointed Grand Mufti said yesterday.

He said use of weapons of mass destruction could also  threaten states beyond the borders of the targeted country and  kill non-combatants — something that would not be allowed even  in a declared war.

But Mufti Ali Gomaa, who issued the ruling days before US  President Barack Obama is due to address the Muslim world from  Cairo, said there was nothing wrong with Muslim countries  acquiring such weapons as a deterrence to potential attackers.

Egypt has US backing for plans to build nuclear power  plants but says it has no desire to make atomic bombs.

Cairo has long called for a Middle East free from nuclear  weapons, an assertion mainly seen aimed at Israel, the only  country in the region believed to have a nuclear arsenal.

“The use by some individuals or groups of weapons of mass  destruction against non-Muslim states is not legally  permissible,” state news agency MENA quoted Gomaa as saying in a  fatwa, or Islamic legal ruling.

The only Muslim country known to have atomic weapons is  Pakistan. Egypt has poor relations with Iran, an Islamic state  that Washington and the West accuses of seeking to build a  nuclear weapon, despite Tehran’s denials.