World leaders are considering how they should deal with Iran following its disputed presidential election and crackdown on protesters.
Imposing new sanctions is one option, but there is little indication the West will push for such measures any time soon.
Following are some possibilities if world leaders do seek new sanctions, and those already imposed by the United States, European Union and United Nations:
* POSSIBLE ADDITIONAL U.S. SANCTIONS:
-- Proposed U.S. sanctions on companies supplying gasoline to Iran would be so potentially damaging to the Iranian economy they would be passed only as a last resort, although Iran says such measures could be bypassed with ease.
-- A gasoline sanctions bill already being considered by the U.S. Congress aims to put pressure on Iran to stop enriching uranium. Despite huge oil reserves, Iran lacks the refining capacity to cater for its highly subsidised local transport market, forcing it to import up to 40 percent of its gasoline.
-- The bipartisan bill, sponsored by the chairman of the House Foreign Affairs Committee, Howard Berman, would ban any company involved in exporting gasoline to Iran from doing business with the United States, be they refiners, shipping firms, banks or insurers. -- U.S. President Barack Obama has set a rough timetable for his outreach to Iran, saying he wants to see progress by the end of the year.
* POSSIBLE EXTRA EU SANCTIONS:
-- Swedish Prime Minister Fredrik Reinfeldt, whose country takes over the EU presidency next week, said on Thursday European sanctions on Iran could be counterproductive.
-- However, France, Germany and Britain are believed to be discussing proposals for fresh EU sanctions. The French daily Le Monde said in January that Britain and France were pushing for EU sanctions on Iran's oil and banking sectors to put pressure on Iran to curtail its nuclear program.
-- A confidential document seen by London's Financial Times and the Italian newspaper Il Riformista in February listed 34 Iranian entities and 10 individuals believed to be linked to covert nuclear or biological weapons programs, the FT said.
-- The individuals listed included the commander and deputy head of the paramilitary Basij force. Among the entities named were Sharif University of Technology, Iran Insurance Company, Iran Air Cargo, Iran Space Agency and the Razi Institute for Serum and Vaccine Production. Six banks were mentioned, including Bank Tejarat, one of Iran's largest commercial banks.
* EXISTING U.N. SANCTIONS:
-- The Security Council has imposed three sets of sanctions on Iran, in December 2006, March 2007 and March 2008.
-- The first covered sensitive nuclear materials and froze the assets of Iranian individuals and companies linked with the nuclear program. 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 programs. In September 2008, the Security Council unanimously adopted a resolution again ordering Iran to halt enrichment, but imposed no more sanctions, due to opposition from Russia and China.
* EXISTING U.S. SANCTIONS:
-- Sanctions imposed after Iranian students stormed the U.S. embassy and took diplomats hostage in 1979 included a ban on most U.S.-Iran trade.
-- In 1995, president Bill Clinton issued executive orders preventing U.S. companies from investing in Iranian oil and gas and trading with Iran. Tehran has found other willing customers.
-- Also in 1995, Congress passed the Iran-Libya Sanctions Act requiring the U.S. government to impose sanctions on foreign firms investing more than $20 million a year in Iran's energy sector. It was extended for five years in September 2006. No foreign firms have been penalized.
-- In October 2007 Washington imposed sanctions on Bank Melli, Bank Mellat and Bank Saderat and branded the Revolutionary Guards a proliferator of weapons of mass destruction.
-- In January 2008 sanctions were imposed on Brigadier-General Ahmed Foruzandeh of the Qods force for fomenting violence in Iraq.
* EXISTING EU SANCTIONS:
-- The EU has imposed visa bans on senior officials such as Revolutionary Guards head Mohammad Ali Jafari, Defense Minister Mostafa Mohammad Najjar and atomic energy chief Gholamreza Aghazadeh, and on top nuclear and ballistic experts.
-- Britain said on June 18 that Iranian assets frozen in Britain under EU and U.N. sanctions totaled 976 million pounds ($1.59 billion).