Al Qaeda Organization in Iraq has slammed as a gathering of infidels an international conference to mark the first anniversary of the Madrid train bombings, and said Islam will prevail. United Nations Secretary-General Kofi Annan told the three-day conference in the Spanish capital Thursday the world must quickly take concerted action against terrorism and deny extremists the chance to carry out a nuclear attack. "How many times do the infidels meet in solidarity against Islam and jihad (holy struggle) ... and stand in the same trench with one thing on their minds; to fight Muslims and abuse them," the group said in a statement posted on a Web site used by Islamists Saturday.Al Qaeda's branch in Iraq said the group was obliged to "terrorize the enemies of God" in a relentless struggle and that it was certain of victory. "No matter what you prepare, o you infidels, you will be defeated and will never be victorious because God has promised us victory," it said in the statement.