"My brothers, we must tell the world that differences don't need to lead to disputes," Abdullah said through a Spanish interpreter, according to The Associated Press. "The tragedies we have experienced throughout history were not the fault of religion but because of the extremism that has been adopted by some followers of all the religions, and of all political systems."

But Abdullah himself, who took over the kingdom after the death of his half brother in 2005, has made remarkable efforts to reach out to other faiths. He met with Pope Benedict XVI late last year - the first time a pope and a reigning Saudi king has met.

And in June, Abdullah convened a religious conference in Mecca where participants vowed to improve relations between Islam's two major branches, Sunni and Shia. Abdullah, at the meeting, had denounced extremism, and said Muslims must show Islam's "good message" to the world.

Besides Christians and Jews, the interfaith gathering also includes Buddhist and Hindu participants.

Prominent religious and political leaders attending the event include evangelist Franklin Graham, Archbishop of Canterbury Rowan Williams, former Vice President Al Gore, American civil rights leader and ex-presidential candidate the Rev. Jesse Jackson, former British Prime Minister Tony Blair and Rabbi David Rosen.