Saudi Arabia's crucial East-West oil pipeline, currently its only outlet for crude exports, was hit in an Iranian attack and other facilities in the kingdom were also targeted, an industry source told Reuters on Wednesday.

The pipeline was diverting around 7 million barrels per day (bpd) from the kingdom's oil heartland in the east to the Red Sea port of Yanbu after Iran effectively shuttered the Strait of Hormuz, trapping huge volumes of oil and gas and sending world energy markets skyrocketing.

Flows through the pipeline are expected to be affected, the source said, adding damage was being assessed. That could exacerbate what experts have called the world's worst energy crisis.

Aramco uses about 2 million bpd domestically, leaving roughly 5 million bpd for export. Yanbu loadings averaged a near-capacity 4.6 million bpd in the week starting March 23, shipping data shows, despite attacks targeting the hub on March 19.

Iran's Islamic Revolutionary Guard Corps said in a statement on Wednesday it hit several targets across the region with missiles and drones, including what it called oil facilities of American companies in Yanbu.