FACTBOX: Sanctions against Iran

(Reuters) - Iran will respond on Friday to incentives offered by six world powers to try to entice Tehran to stop enriching uranium, which they fear could result in a nuclear bomb.

European Union states agreed on June 23 to impose new sanctions on Iran, including an asset freeze on its biggest bank, over its refusal to meet demands to curb its nuclear program.

Following are some details about the sanctions and those already imposed by the U.N. Security Council and the United States.

* WHAT DO THE NEW EU SANCTIONS INCLUDE?

-- The new sanctions will target businesses and individuals that the West alleges are linked to Iranian nuclear and ballistic programs.

-- There are visa bans on senior officials such as Revolutionary Guards head Mohammad Ali Jafari, Defense Minister Mostafa Mohammad Najjar and atomic energy chief Gholamreza Aghazadeh.

-- Iran's biggest bank, Bank Melli will face an asset freeze under the moves, while visa bans will target "very senior experts" inside Iran's nuclear and ballistic programs.

* WHAT SANCTIONS HAVE ALREADY BEEN IMPOSED?

U.N. SANCTIONS:

-- The U.N. Security Council imposed three sets of sanctions on Iran, in December 2006, March 2007 and March 2008.

-- The first round covered sensitive nuclear materials and froze the assets of Iranian individuals and companies associated with the program. It gave Iran 60 days to suspend uranium enrichment, a process which can be used to make nuclear power plant fuel or bomb material. Iran did not stop.

-- The second round included new arms and financial sanctions. It extended an asset freeze to 28 additional groups, companies and individuals engaged in or supporting sensitive nuclear activities or development of ballistic missiles.

-- State-run Bank Sepah and commanders and firms controlled by Iran's Revolutionary Guards, including commanders of one of its units, the Qods Force, were included on the list.

-- The resolution invoked Chapter 7, Article 41 of the U.N. Charter, which makes most of its provisions mandatory but excludes military action. Iran again failed to meet a 60-day deadline to halt enrichment.

-- On March 3, 2008, the U.N. Security Council imposed the third round of sanctions for refusing to suspend sensitive nuclear activities. Tehran dismissed the council's decision as illegal and illegitimate.

-- The sanctions resolution called for more travel and financial curbs on Iranian individuals and companies and makes some restrictions mandatory.