<h1>Nuclear negotiations postponed; talks mediated by Oman to constrain Iran's programme in exchange for sanctions relief.</h1> Planned U.S.-Iran nuclear negotiations were postponed at Oman's request and will be rescheduled by mutual agreement; Iran affirmed commitment to a fair agreement while a U.S. source said Washington had not formally confirmed participation but anticipated future talks. The talks aim to limit Iran's nuclear programme in exchange for lifting economic sanctions, set against the context of the 2015 nuclear deal, the U.S. withdrawal in 2018, regional hostilities, U.S. military action against Houthi forces, and recent security incidents in Iran.