Iranian officials have raised the issue during talks with Oman, which has been acting as an intermediary between Tehran and the US. Meanwhile, Saudi Arabia, Turkey and Pakistan signed a trilateral defence agreement under which an attack on any of one of the three countries would be treated as an attack on all. The agreement was announced following talks in the Saudi city of Mecca between Saudi Crown Prince Mohammed bin Salman. Camera Icon Saudi Crown Prince Mohammed bin Salman and Turkey's Recep Tayyip Erdogan have made a defence pact. Tehran has attacked US bases and civilian infrastructure in Saudi Arabia, Kuwait, Bahrain, Qatar, the United Arab Emirates, Oman, Jordan and Israel.