U.S. President Barack Obama signed a law last week imposing tough new sanctions on Iran's banking and energy sectors, hoping to curb Tehran's nuclear enrichment activities.

The West fears Iran's nuclear work could be used for bomb-making, which Tehran denies saying it is for energy production.

Some major oil companies have stopped jet fuel supplies to Iranian aircraft outside Iran and the London insurance market will not cover petroleum shipments going to Iran.

Following are the key points in the latest developments to fuel supplies to Iran:

U.S. Sanctions
• U.S. laws would sanction any company worldwide that exports gasoline or other refined petroleum products to Iran.

• Washington has not spelled out whether its new sanctions are intended to require firms to refuse to fuel Iranian jets at airports in third countries.

• The U.S. does not import crude oil from Iran.

Europe
• European Union foreign ministers will adopt tighter sanctions against Iran next week, including measures to block oil and gas investment and curtail its refining and natural gas capability.

Jet Fuel
• Oil major Royal Dutch Shell will not renew its contracts to supply Iran Air with jet fuel in response to pressure from the U.S. to cease business with the Islamic republic, an industry source said earlier in July.

• Oil major BP has ceased supplying jet fuel to Iran Air at Germany's Hamburg airport, both parties confirmed earlier in July.

• Industry sources said earlier in July French major Total supplies jet fuel to Iranian aircraft.

Gasoline Exports
• Iran is the world's fifth-largest crude exporter and a member of the Organization of the Petroleum Producing Countries (OPEC). But it has to import some refined oil products to meet domestic demand due to a lack of sufficient refining capacity.

• Lloyd's of London will not insure or reinsure petroleum shipments going into Iran.

• Some shipping associations have also introduced clauses enabling ship owners to refuse to deliver refined petroleum cargoes to Iran, which freight players say will lead to higher costs and fewer providers of cargoes. This means Iran would suffer delays in getting gasoline and faces more complicated transactions to secure supplies.

• Shipping and oil trading sources said the owner of a gasoline tanker refused to allow a vessel to sail to Iran from Turkey earlier in July.

• There has been other unconfirmed speculation that more cargoes were diverted.

• The Islamic Republic is buying around half of its July gasoline imports from Turkey and the rest from Chinese sellers, oil traders said, as most other suppliers have stopped selling due to the U.S. sanctions.

• Many gasoline sellers stopped trading with Iran in anticipation of the U.S. sanctions. French oil major Total in June joined the growing list of those that had stopped sales.

• Shell, BP, India's Reliance Industries and independent Swiss trader Glencore are among suppliers that have already either stopped fuel sales to Iran or have made a decision not to enter into new trading agreements with Iran.

• Russian oil major Lukoil will cease gasoline sales to Iran, industry sources said in April.

• Malaysia's Petronas has stopped supplying gasoline to Iran, a company spokesman said in April.

Upstream Projects In Iran
• Repsol has pulled out of a contract it won with Shell to develop part of the South Pars gas field in Iran.

• Italy's oil and gas major Eni is handing the operation of Darkhovin oilfield in Iran to local partners to avoid U.S. sanctions, Eni told U.S. authorities on April 29.