UNITED NATIONS (Reuters) - Syria remains the top destination for Iranian arms shipments in violation of a U.N. Security Council ban on weapons exports by the Islamic Republic, according to a confidential report on Iran sanctions-busting seen by Reuters on Wednesday. Iran, like Russia, is one of Syria's few allies as it presses ahead with a 14-month old assault on opposition forces determined to oust Syrian President Bashar al-Assad. News of the panel's report came as Tehran and the U.N. ...

VIENNA (Reuters) - Iran is installing more centrifuges in an underground plant but does not yet appear to be using them to expand higher-grade uranium enrichment that could take it closer to producing atom bomb material, Western diplomats say. They say Iran's production of uranium refined to a fissile concentration of 20 percent, which it started two years ago, seems to have remained steady in recent months after a major escalation of the work in late 2011 and early this year. ...

ATHENS (Reuters) - IMF chief Christine Lagarde warned of "extremely expensive" consequences were Greece to leave the euro zone, a once taboo possibility that European leaders have begun to discuss openly after the nation descended into political chaos. Fears that Greece's dire state could drag the euro zone deeper into crisis rattled financial markets across the globe, as a little-known judge was installed to head an emergency government which will lead the nation to new elections on June 17. ...