Saudi oil attacks an 'act of war' says US Secretary of State

US Secretary of State Mike Pompeo on Wednesday described strikes on key Saudi oil installations as an "act of war", reiterating that it was an "Iranian attack".

"This was an Iranian attack," he told reporters on his plane before landing in the western city of Jeddah, calling it "an act of war".

He added there was no evidence the attacks had been launched from Iraq, amid media speculation the drones had been fired from there.

Pompeo landed in the Red Sea city of Jeddah, where he was scheduled to meet with Saudi Crown Prince Mohammed bin Salman.

He is set to travel to the UAE on Thursday to meet with Abu Dhabi's powerful Crown Prince Sheikh Mohammed bin Zayed Al-Nahyan.

Both nations are US allies and have been fighting against the Houthis in Yemen.

Saudi Arabia alleged on Wednesday that Iranian cruise missiles and drones attacked the heart of the kingdom's oil industry, showing journalists the remains of the weapons while stopping short of directly accusing Iran of launching the assault.

Iran has denied involvement in the assault, which was claimed by Yemeni rebels, and has threatened the US that it will retaliate "immediately" if Tehran is targeted over the attack.

The news conference by Saudi military spokesman Col. Turki al-Malki comes after a summer of heightened tensions between Iran and the US over President Donald Trump unilaterally withdrawing America from Tehran's 2015 nuclear deal with world powers.