Iraq's president said Wednesday he had reached a security agreement with Iran, which the United States accuses of fueling the chaos in the war-torn country. Iran's president called on countries to stop backing "terrorists" in Iraq and for the Americans to withdraw. Tehran is believed to back some of the Shiite militias blamed in the vicious sectarian killings that have thrown the country into chaos. The United States has said the Iraqi government should press Iran to stop interfering in its affairs in a bid to calm the violence. Presidents Jalal Talabani of Iraq and Mahmoud Ahmadinejad of Iran held talks Wednesday hours before U.S. President George W. Bush was due to meet with the Iraqi prime minister in Jordan in talks aimed at finding a solution to Iraq's spiraling bloodshed.