The statement, which was posted on Tuesday on a website known for hosting fighters' material, said the "Arab League initiative is a new conspiracy to save their American master under the pretext of national reconciliation, maintaining Iraq's unity and protecting the Sunnis against falling under Iranian influence".
The Arab League plans to hold a reconciliation conference at its Cairo headquarters but a date has not been set. League Secretary-General Amr Moussa is expected to travel to Iraq on Thursday, his first visit since Saddam Hussein's ouster, to try to organise it.
The al-Qaida in Iraq statement, which could not be authenticated, said Moussa was going to Iraq to "convince the Sunnis to enter the political 'game' with the Shia ... in exchange for stopping the tide of jihad in the Sunni areas".
"The Crusaders have found themselves drowned in a bottomless swamp ... they have found no better allies than the old Arab agents and their League," it added.
The United States has welcomed the Arab League reconciliation initiative and urged Iraq's neighbours to lend diplomatic support to Iraq's people and its government.