As the Biden administration pushes forward with a new diplomatic agreement designed to end years of open conflict with Iran, Secretary of State Marco Rubio has embarked on a high-stakes regional tour of Gulf Arab allies, with the BBC’s senior state department correspondent Daniel Bush embedded with the traveling delegation. Longstanding partners in the Gulf Cooperation Council have emerged as some of the most vocal skeptics of a U.S.-brokered peace deal with Iran, raising urgent concerns about provisions that could ease economic sanctions on Tehran and allow it to resume limited nuclear enrichment activities. These allies fear the deal would strengthen Iran’s regional influence, enable its support for proxy armed groups across the Middle East, and leave them at a strategic disadvantage against a resurgent Iranian state. The core goal of Rubio’s trip is to address these fears head-on, offering security guarantees and diplomatic concessions to shore up confidence among U.S. partners, while making the case that ending the long-running standoff with Iran serves the long-term interests of the entire region. Many diplomatic analysts are closely watching the outcome of the tour, as Rubio’s ability to unify U.S. allies around the proposed deal will play a critical role in determining whether the agreement can be finalized and implemented successfully. The tour comes at a moment of heightened regional tension, with recent exchanges of fire between Iranian proxies and Israeli forces adding new urgency to diplomatic efforts to de-escalate the broader conflict.