Donald Trump has hinted that the US believes Iran is responsible for attacks on oil plants in Saudi Arabia over the weekend that raised fears of a fresh conflict in the Middle East. "It would look the most like it was Iran," he told reporters at the White House.

Iran has denied responsibility for the attacks which damaged the world's biggest crude processing plant in Saudi Arabia and triggered the largest jump in crude prices in decades. Iran's president, Hassan Rouhani, suggested on Monday that "Yemeni people" were to blame.

