Janet Jalil

And secondly, there is the risk of massive Iranian retaliation.

And the Saudis had a bit of a wake-up call in September 2019 when, having joined in the Yemen war to try and beat the Houthis,

They then got hit by a flurry of drones launched from Iraq by Iranian-backed proxies.

Iran always denied it, but I think everybody assumes it was Iranian-backed proxies that launched these drones at Saudi Arabia's petrochemical facilities.

And that knocked out half of Saudi's export capacity for several days.

Now, that was just a taste of what could possibly come.

So the Saudis know that they are vulnerable.

They've got good air defences.

They were able to shoot down the eight ballistic missiles that Iran fired at Riyadh a couple of days ago.

But not everything is able to be shot down.

Some things get through, and the damage to their critical national infrastructure could be catastrophic.

Frank Gardner in Doha.

Well, we've already seen how damaging attacks on energy infrastructure can be, with this week's soaring gas and oil prices and stock market falls after that Iranian attack on Qatar's main site for producing liquefied natural gas.

Our business reporter, Nick Marsh, told me more about the extent of the damage at this highly important gas facility and the impact it's likely to have on our energy bills.

And briefly, we saw energy prices spike yesterday.

What's it like today?

Nick Marsh.

And there's been a warning that the world faces its greatest ever energy threat from the Iran war.

The International Energy Agency says the disruption to supplies is the largest in oil market history.

And it's urged governments to look at ways of reducing demand, such as cutting speed limits and encouraging people to work from home more and to fly less.