Tanker markets are braced for fallout from attacks on two major Saudi Arabian oil production facilities which has hit more than half the output of the world’s biggest exporter.

The attacks by Yemen’s Houthi rebels on Saturday morning are said by Saudi officials to have knocked out production of 5.7m barrels a day, more than 5% of global production.

One of the targets was the Abqaiq plant that processes crude from the world’s largest conventional oilfield, Ghawar, and for export to the terminals at Ras Tanura - the world’s biggest offshore oil loading facility - and Juaymah.