Disruptions to trade come as sanctions on Iran begin to tighten. The European Union and US have both introduced trade restrictions on the Central Bank of Iran.
"Rabobank has pulled out of financing grain trades that are destined for Iran," a bank spokeswoman said. Rabobank is one of Europe’s largest provider of agricultural commodity financing.
"Our bank hasn’t touched anything that is destined for Iran," a European grains trader said, adding that as far as he was aware all European banks had halted dealings with the country.
"All physical traders have stopped trading with Iran because of the country’s difficulties in obtaining letters of credit," the trader said.
Iran typically imports around 5 million tonnes of grain a year, most of which is corn.
According to official port records, at least 11 vessels carrying foodstuffs have been waiting for several days to dock at Iranian ports, due to a "lack of readiness of cargo owners." It is unclear if the delays are tied to sanctions.