Oil prices edged up on Monday after a breakdown in diplomatic ties between Saudi Arabia and Iran that some speculated could result in supply restrictions, although gains were tempered by data showing some of Asia’s largest economies are struggling. Saudi Arabia, the world’s biggest oil exporter, cut diplomatic ties with Iran on Sunday in response to the storming of its embassy in Tehran following Riyadh’s execution of a prominent Shi’ite cleric on Saturday. Fellow Gulf producer Bahrain said on Monday it too would cut ties with Iran.