Iran's foreign minister made an unscheduled visit to Damascus Thursday, a day after the UN Security Council voted to unilaterally establish an international tribunal to prosecute suspects in the assassination of Lebanon's former Prime Minister Rafik Hariri. A UN investigation has implicated Syria in Hariri's assassination in 2005 when the Syrian army controlled Lebanon. Syria has denied involvement. Iranian Foreign Minister Manouchehr Mottaki held talks with Syrian President Bashar Assad and was due to meet with other senior Syrian officials. He did not speak to reporters. Syria is Iran's closest Arab ally.