For Iran to resume business with the global banking world - for the first time since 2012 - its banks need to be linked to overseas lenders on SWIFT. The system, the Society for the Worldwide Interbank Financial Telecommunications, is used to transmit payments and letters of credit. A senior official with Iran's central bank said that all the private and state-owned banks have taken the necessary bureaucratic steps, regarding rejoining the SWIFT system. While international banks are expected to link up with their Iranian counterparts via SWIFT, Iran will also be looking to encourage foreign institutions to expand involvement in the country’s financial system. But for many foreign banks, there are concerns about being caught up in ongoing U.S. sanctions.