The European Union will establish a special payment channel to allow companies to continue to trade with Iran and avoid US sanctions.
The 'special purpose vehicle' (SPV) to facilitate payments related to Iran's exports, notably oil, and imports was unveiled following a ministerial meeting at the UN in New York.
Britain, China, France, Germany, Russia, Iran and the EU all supported the move to protect businesses from Donald Trump's sanctions.
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In a joint ministerial statement, they said: “Mindful of the urgency and the need for tangible results, the participants welcomed practical proposals to maintain and develop payment channels, notably the initiative to establish a special purpose vehicle, to facilitate payments related to Iran's exports (including oil) and imports, which will assist and reassure economic operators pursuing legitimate business with Iran.”
The US pulled out of the 2015 Iran nuclear deal in May and announced sanctions against the country would be reimposed.
Iran had agreed to curb its nuclear programme in return for international sanctions being lifted but Trump withdraw from the Obama administration deal.
A number of European firms, including oil giant Total, Peugeot, Volvo and Daimler have already suspended operations in Iran ahead of the sanctions – set to be imposed in November.
EU foreign policy chief Federica Mogherini said the SPV would mean EU member states setting up a legal entity to facilitate financial transactions with Iran.
She added it would allow European companies to continue to trade with Iran, in accordance with EU law, and could be opened to other countries.
Trump snubbed a meeting with Iranian president Hassan Rouhani as world leaders gathered at the UN summit in New York.
Taking to Twitter, he said: “Despite requests, I have no plans to meet Iranian President Hassan Rouhani. Maybe someday in the future. I am sure he is an absolutely lovely man.”