U.S. Secretary of State Marco Rubio said Iran has agreed to a “certain format” for talks with Washington ahead of a high-level meeting in Oman, as both sides test the waters for possible diplomacy. Speaking in Washington, Rubio said the U.S. is ready to engage despite doubts over whether a deal is achievable, stressing there is no harm in trying. He also criticised Iran’s clerical leadership, arguing it does not represent the Iranian people. The talks, shifted from Turkey to Oman, are expected to focus narrowly on Iran’s nuclear programme and the potential lifting of sanctions.