The United States warned Syria on Thursday to abide by a United Nations arms embargo meant to stop Hizbullah from rearming itself after its month-long war with Israel, and dismissed Syrian objections to international peacekeepers as "preposterous." "All countries must obey the arms embargo," under the United Nations Security Council resolution that set a cease-fire this month, State Department spokesman Gonzalo Gallegos said. "It is a singular duty for Syria, as the one country apart from Israel that borders Lebanon, to do so." Syria is a Hizbullah benefactor that was largely left out of diplomacy during the 34-day war. On Wednesday, Syrian President Bashar Assad called any deployment of multinational troops along his border a "hostile" affront to Syria. "First, this means creating hostile conditions between Syria and Lebanon ," Assad told Dubai Television in an interview aired Wednesday. "Second, it is a hostile move toward Syria and naturally it will create problems." The notion that the troops are a threat to Syria "is preposterous," the State Department's Gallegos said in Washington. "We call on the Syrian regime to fulfill its international obligations." Syria has also indicated it might impose a punitive blockade of Lebanon. "They will close their borders for all traffic in the event that UN troops are deployed along the Lebanon-Syria border," Finland's Foreign Minister Erkki Tuomioja said after meeting his Syrian counterpart, Walid Moallem, in Helsinki. Finland holds the rotating presidency of the European Union. The Bush administration refused to talk directly to Syria during the negotiations to end the Israeli-Hizbullah fighting. In the complex diplomacy now underway seal and strengthen the fragile UN-brokered cease-fire, the administration is wary of new efforts by Syria to assert control in Lebanon. The United States pulled its ambassador out of Syria last year after the assassination of a Lebanese politician who had sought to steer his nation away from three decades of Syrian military and political control.