In a statement on Friday, the organization said road maintenance crews restored traffic on damaged routes in less than 12 hours after attacks hit transport infrastructure, including several bridges in the south of the country.
It said bypasses were rapidly constructed around the damaged sections, allowing vehicles to resume using the affected roads.
"Despite the enemy's savage attacks on transportation infrastructure, all road routes across the country remain open and traffic is flowing," the statement said.
The announcement came after criminal attacks by the terrorist US military targeted civilian infrastructure across several Iranian provinces from late Thursday into early Friday, including several bridges, killing eight people and injuring 20 others.
The attacks primarily struck the provinces of Hormozgan, Bushehr, Sistan and Baluchestan, Khuzestan and Lorestan. They followed US President Donald Trump's threats to target Iran's civilian infrastructure, including bridges and power plants, amid the international community's silence over US war crimes.
Hormozgan Province sustained the heaviest casualties.
Six bridges in Khamir County were struck, damaging key transport routes linking Bandar Abbas, Bandar Khamir and Lar, as well as roads through Latidan, Kahorestan, Keshar and Maru village.
The strikes also hit a railway branch station in Bandar Abbas, while a separate attack targeted the Allah Akbar Hill residential neighborhood in the city.
The bridge and railway attacks appeared aimed at severing Bandar Abbas, Iran's largest port, from road and rail links connecting it to the country's central regions and the capital, Tehran. The strikes appeared intended to disrupt the movement of goods needed by Iran's population of around 90 million.
Iran's Health Ministry said on Friday that at least 38 people had been killed and more than 400 injured in the latest US attacks. Forty-seven people remain hospitalized, according to the ministry.
Press TV