Donald Trump says he has approved the release of US strategic petroleum reserves “if needed” to stabilise energy markets after an attack on Saudi Arabian energy facilities.

The US president tweeted that the attacks could have an impact on oil prices and the final amount of the release, if any, would be “sufficient to keep the markets well-supplied”.

The authorisation alone could help prevent a spike in oil prices after the attack led to suspension of more than 5% of the world’s daily crude oil production.

The Trump administration has blamed the attack on Iran.

The federally owned petroleum reserve of hundreds of millions of barrels of crude oil has only been tapped three times, most recently in 2011 amid unrest in Libya.