Escalation would follow oil passing $100 a barrel again and Houthi strikes on Saudi tankers in the Red Sea

The US president, Donald Trump, has said he is close to deciding whether to launch “a massive attack” against Iran, on a scale larger than strikes already witnessed during the months-long conflict with Tehran.

Speaking to the Axios news site Trump said: “I am considering a massive attack. Bigger than ever before. I am close to making a decision. We are all set for it.”