Islamic Republic of Iran Shipping Lines (IRISL), a major shipping company, and oil producer Iranian Offshore Oil Co (IOOC) have reached preliminary deals with South Korean shipyards for orders worth around $2.4 billion, a report said.

The agreements are part of Iran's efforts to make a comeback in global shipping after the lifting of international sanctions earlier this year, a source was quoted as saying in the Wall Street Journal report.

The source added that the yards are making slots available to the Iranians starting in 2018 and 2019, and the Iranians are trying to make the 20 per cent down payments through oil state-to-state deals to finalise the orders.

If the oil deals work out with the South Korean government, Seoul can then give the necessary guarantees for the down payment to the yards, said the report.

A second source noted that options for down payments are being discussed and the orders are expected to be completed by the end of summer.