Iran will hold talks in Istanbul on Friday with European parties to their now-moribund 2015 nuclear deal, two European and an Iranian diplomatic source said on Tuesday, The talks among senior diplomats come as both sides seek to position themselves ahead of an expected fifth round of U.

Nadergholi Ebrahimi has asked Supreme Leader Khamenei to rethink Iran's nuclear policy if negotiations with the U.S. collapse.

A fourth round of nuclear talks between the United States and Oman have produced encouraging results for the Trump administration, a senior official told reporters Sunday.