Factbox: U.N., U.S. And EU Sanctions On Iran

The United Nations Security Council voted to impose a fourth round of sanctions on Iran on Wednesday.

Following are some details of the sanctions imposed on Iran by the United Nations, United States and the European Union.

* U.N. SANCTIONS:

-- The Security Council has imposed four sets of sanctions on Iran, in December 2006, March 2007, March 2008 and June 2010.

-- The first covered sensitive nuclear materials and froze the assets of Iranian individuals and companies linked with the nuclear programme. It gave Iran 60 days to suspend uranium enrichment, a deadline Iran ignored.

-- The second included new arms and financial sanctions. It extended an asset freeze to 28 more groups, companies and individuals engaged in or supporting sensitive nuclear work or development of ballistic missiles, including the state-run Bank Sepah and firms controlled by the Revolutionary Guards.

-- The resolution invoked Chapter 7, Article 41 of the U.N. Charter, making most of its provisions mandatory but excluding military action. Iran again ignored an order to halt enrichment.

-- The third measure increased travel and financial curbs on individuals and companies and made some of them mandatory. It expanded a partial ban on trade in items with both civilian and military uses to cover sales of all such technology to Iran, and added 13 individuals and 12 companies to the list of those suspected of aiding Iran's nuclear and missile programmes. In September 2008, the Security Council unanimously adopted a resolution again ordering Iran to halt enrichment, but has not imposed more sanctions due to opposition from Russia and China.

-- In March 2010, the U.S. agreed with Britain, France and Germany on a draft proposal for a fourth round of sanctions and circulated it to Russia and China for comments.

-- The Security Council resolution passed on Wednesday calls for measures against new Iranian banks abroad if a connection to the nuclear or missile programs is suspected, as well as vigilance over transactions with any Iranian bank, including the central bank.

-- It also expands a U.N. arms embargo against Tehran and blacklists three firms controlled by Islamic Republic of Iran Shipping Lines and 15 belonging to the Islamic Revolutionary Guard Corps. The resolution also calls for setting up a cargo inspection regime similar to one in place for North Korea.