Many members of parliament may vote against his choice of cabinet members tomorrow, but the power struggle does more than hamper Mr Ahmadinejad’s ability to form a new government. It also raises a challenge for Barack Obama. As the price for taking a strong line over settlements, Mr Obama has been placatory with Israel’s prime minister, Benjamin Netanyahu, about the need to face up to Iran. Mr Netanyahu has made no secret of his desire to bomb Iran’s nuclear facilities. One way and another, Mr Obama has been bounced into setting an early September deadline for Iran to reply to the US offer of talks. If Iran misses it, congressmen are preparing fresh legislation to cut off the country’s imports of petrol and other refined oil products.