Iran repelled a large cyber attack on its infrastructure on Sunday, said the head of its Infrastructure Communications Company, a day after a powerful explosion damaged its most important container port and another round of talks with the US over Tehran’s disupted nuclear programme.

“One of the most widespread and complex cyber attacks against the country’s infrastructure was identified and preventive measures were taken,” Behzad Akbari said on Monday, according to semi-official Tasnim news agency, without giving more detail.

Tehran and Washington concluded a third round of nuclear talks on Saturday in Oman, on the same day Iran’s biggest port of Bandar Abbas was rocked by a large explosion whose cause remains unknown.

Chemicals at the port were suspected to have fuelled the explosion, but the exact cause was not clear and Iran’s Defence Ministry denied international media reports that the blast may be linked to the mishandling of solid fuel used for missiles.

Iran has in the past accused its arch-foe Israel of being behind cyber attacks. Israel’s Prime Minister Benjamin Netanyahu said on Sunday that Iran’s nuclear infrastructure should be entirely dismantled - not just limited to prevent the development of nuclear weapons.

In 2021, a large cyber attack on Iranian petrol stations was said by Tehran to likely be caused by Israel. In 2023, a similar but larger cyber attack disrupted about 70% of petrol stations, with a group called “Predatory Sparrow” claiming the attack as retaliation to “the aggression of the Islamic Republic and its proxies in the region.”