Iran’s claims that it had nothing to do with the attack on Saudi Arabia’s oil facilities no longer seem credible after the compelling evidence Saudi officials have produced of the weaponry that was used.
In the immediate aftermath of last weekend's attacks on Saudi Arabia's Khurais oil field and the Abqaiq oil processing facility, leaders of the Iranian-backed Houthi rebels, who have carried out a number of missile and drone attacks against predominantly civilian targets in Saudi Arabia, said they were responsible.
But following detailed analysis of last Saturday's attack by US and Saudi military experts, there is now little doubt in Washington and Riyadh that ultimate responsibility for the operation, which knocked out nearly 50 per cent of the country's oil processing capacity, lies with Tehran.
As Colonel Turki Al Malki, the Saudi defence ministry spokesman said during a briefing on the attack earlier this week, it was "unquestionably sponsored by Iran". A similar conclusion has been reached by US Secretary of State Mike Pompeo who, prior to meeting Saudi Crown Prince Mohammed bin Salman at the Red Sea city of Jeddah on Wednesday, told journalists "this was an Iranian attack" that amounted to an "act of war". Washington is now planning to impose a further round of sanctions against Tehran in retaliation.
Moreover, Saudi defence officials have provided detailed evidence demonstrating the Iranian-made weapons that were used in the attack, including a number of cruise missiles and delta wing drones that also belong to the Iranian military.
About the only issue that still needs to be resolved is to determine the launch site, with Saudi officials saying that initial indications are that they were fired from the north, not the south as the Houthis have claimed. American officials have indicated they were fired from western Iran, near the border with Iraq, which is directly north of Abqaiq. Scientists are trying to extract GPS data from the fallen missiles to see if that might provide clues as to where they and the drones originated from.
Yet while the precise of the origin of the attack is still to be confirmed, Saudi officials are insistent that it could not have been mounted from Houthi-controlled territory in Yemen because of the distances involved. In his media briefing, Col Al Malki said the missiles’ maximum 690-kilometre range was too short for them to have been fired from Houthi territory.
Certainly, irrespective of the final outcome of the investigation into the attack, it is clear that by targeting Saudi Arabia's critical oil infrastructure, the perpetrators were aiming not just to disrupt Saudi Arabia but the entire global economy.
For at a time when Iran’s economic prospects have been devastated by the sanctions imposed by the US, following president Donald Trump’s decision to withdraw from the controversial 2015 nuclear deal, Iran is keen to show that it is not the only country that will suffer as a result of the deepening stand-off between Washington and Tehran.
One of the key consequences of Mr Trump’s decision to withdraw from the deal is that it has played into the hands of the regime’s hardliners, who were always sceptical of the deal negotiated by more moderate figures in Tehran such as foreign minister Mohammad Javad Zarif.
Now that they are back in the ascendant, the hardliners are determined to demonstrate that, despite the sanctions, Iranian power and resolve have not been diminished.
It is to this end that Tehran has invested heavily in its numerous proxies throughout the region in an attempt to strengthen and consolidate its presence in the Middle East. Thus Iran’s Islamic Revolutionary Guard Corps has been busy working with terror organisations such as Hezbollah in Syria and Lebanon while supporting pro-Iranian Shia militias in southern Iraq. Tehran’s continued support for the Houthi rebels in their bid to seize control of Yemen also needs to be viewed in the context of Tehran’s regional power grab.
Iran's reliance on using proxies to do its bidding, moreover, is a convenient means of covering its tracks. For all Tehran's bluster, its military capabilities are no match for the US and its allies in the Gulf, which have increased their strength considerably in recent months, following Tehran's attempts to disrupt merchant shipping in the Strait of Hormuz. If Iran were ever reckless enough to involve itself in a conventional military confrontation with the US, it would suffer devastating consequences.
Therefore Iran prefers to indulge in what is known as hybrid warfare, relying on proxies and other non-state actors to do its bidding so that, as with the latest attacks against Saudi Arabia, it can deny any involvement.
The only problem with this type of approach, as Tehran is discovering to its cost, is that, with modern technology, it is much easier to detect who is really driving events.
Thus, while it would be extremely convenient for Iran if the Houthis were able to claim credit for the Saudi attacks, modern intelligence-gathering systems such as spy satellites mean it is far more difficult to conceal the truth.
Consequently, if Iran genuinely believed that it could escape blame for the attacks on Saudi Arabia’s oil infrastructure, it is going to be sorely disappointed.
For no matter how much Tehran might protest its innocence, all the evidence points to Iranian culpability so that, with the Trump administration determined to take punitive action, it will be Iran, not Saudi Arabia, that ultimately suffers most as it is subjected to even greater economic hardship.
Con Coughlin is the Telegraph’s defence and foreign affairs editor