Iraq's prime minister made little headway in easing Iranian opposition to a U.S.-Iraqi security pact, as Iran's supreme leader told him Monday that American troops must leave the country. The deal, which is still under negotiation, could lay the groundwork for a long-term U.S. military presence in Iraq. The Iranians fear the deal would solidify U.S. influence in Iraq and give American forces a launching pad for military action against them. Iraqi Prime Minister Nouri al-Maliki met over three days with Iranian leaders in Tehran, trying to ease the neighboring country's opposition to the agreement - apparently hoping to stop Iranian denunciations while assuring the Iranians that a deal would pose no threat to their security. But in talks Monday, Iranian supreme leader Ayatollah Ali Khamenei made clear his rejection of any agreement. He said "occupiers who interfere in Iraq's affairs through their military and security might" are the main cause of Iraq's problems and the "main obstacle in the way of the Iraqi nation's progress and prosperity." He told al-Maliki that Iraqis must "think of a solution to free" the country from the U.S. military, and he vowed that "America's dream for Iraq will not come true," according to state-run television. Al-Maliki returned to Iraq later Monday, ending his second trip to Tehran in a year. ...