The country’s oil ministry, national oil company and a number of other companies affiliated with the ministry were hit by a cyber-attack on Sunday, according to Iranian news agency Mehr.
Iran’s deputy oil minister said the facilities were taken offline and a special cyber response team was set up.
Around 80 per cent of Iran's daily 2.2 million barrels of crude export goes through Kharg Island, located off Iran’s southern coast, which was one of the facilities attacked.
Iran has often claimed it is involved in a long-running technological war with the United States and Israel. The most recent similar attack happened in 2010, when the country’s nuclear program suffered a big blow from a worm called Stuxnet.