When Saudi Arabia’s Oil Minister Khalid al-Falih made his debut at Opec’s 2 June meeting in Vienna, many had expected him to turn the event into a showdown between the kingdom and its arch-­ideological rival Iran.

The notion of a clash involving Opec’s two main pillars was fuelled by that fact that Falih is a close confidant of powerful Saudi Deputy Crown Prince ­Mohammed, who has made the economic and political isolation of Iran the main plank of his foreign policy.