US sanctions are preventing aid from reaching Iran after flash flooding claimed at least 70 lives and left 86,000 people homeless, according to the Red Crescent Society.

The humanitarian organisation said it was unable to obtain foreign financial assistance for the victims of the disaster as a result of the “inhuman” measures reintroduced by Donald Trump last year.

Instead the Red Crescent are reliant on non-financial help, such as a recent rescue package of boats and equipment worth €300,000 (£260,000) from Germany.

“No foreign cash help has been given to the Iranian Red Crescent society,” the group said in a statement. “With attention to the inhuman American sanctions, there is no way to send this cash assistance.”

It came after Iranian foreign minister Mohammad Javad Zarif accused the US of “economic terrorism” and claimed that secretary of state Mike Pompeo was “trying to take abnormal and politically-driven advantage of the suffering of human beings afflicted by natural disasters.”

Flash flooding kills at least 19 in Iran Show all 10 1 /10 Flash flooding kills at least 19 in Iran Flash flooding kills at least 19 in Iran Cars are piled after being swept up in flash flooding in Shiraz in south-central Iran AFP/Getty Flash flooding kills at least 19 in Iran Vehicles are swept to the roadside in flash flooding in Shiraz in south-central Iran Reuters Flash flooding kills at least 19 in Iran Military vehicles rescue people after flash flooding in the north Iranian of Agh Ghaleh AP Flash flooding kills at least 19 in Iran The northern Iranian village of Agh Ghaleh - shown here on March 23 - has been flooded over the past week AFP/Getty Flash flooding kills at least 19 in Iran The northern Iranian city of Agh Ghaleh - shown here on March 23 - has been flooded over the past week AFP/Getty Flash flooding kills at least 19 in Iran Clean-up efforts after flash flooding in Shiraz in south-central Iran Reuters Flash flooding kills at least 19 in Iran Residents of the northern Iranian village of Agh Ghaleh - shown here on March 23 - walk in a flooded street. The town has been flooded over the past week AFP/Getty Flash flooding kills at least 19 in Iran Cars are piled after being swept up in flash flooding in Shiraz in south-central Iran AFP/Getty Flash flooding kills at least 19 in Iran Cars are piled after being swept up in flash flooding in Shiraz in south-central Iran AP Flash flooding kills at least 19 in Iran The northern Iranian city of Agh Ghaleh - shown here on March 23 - has been flooded over the past week AFP/Getty

Mr Pompeo had earlier accused Iran’s clerical establishment of “mismanagement in urban planning and in emergency preparedness”, while indicating the US was willing to assist the relief effort.

The floods, which mainly affected the northeast and southwest of the country, were caused by exceptionally heavy rainfall which has hit the country since 19 March.

Iran’s government has promised to compensate all losses but the budget is already stretched due to a sharp reduction in oil exports as a result of sanctions.

The US is also said to be planning to ramp up the pressure on Iran even further by designating the Revolutionary Guard a “foreign terrorist organisation”.

Around 60 groups, such as al-Qaeda, Isis and Hezbollah, have been designated by the defence department as “foreign terrorist organisations”, but this would be the first to apply to a state-run military.

However officials have raised concerns that the move could complicate US diplomatic efforts and may even prompt Iran to retaliate against US forces in the region.

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