U.S. diplomatic efforts, including recent shuttle visits by envoys Jared Kushner and Steve Witkoff to Moscow and Kyiv followed by a Trump-Putin phone call, have produced no scheduled trilateral summit with Zelenskyy before year-end. Core barriers include entrenched Russian demands for Ukrainian territorial concessions in Donbas and limits on NATO ties, contrasted with Kyiv's insistence on security guarantees and no unilateral withdrawals. Trump has publicly identified personal animosity between Putin and Zelenskyy as the primary obstacle, while battlefield advances, resumed strikes, and skepticism from intelligence assessments about Moscow's seriousness have kept bilateral or three-way leader meetings off the immediate agenda. These factors align with trader consensus reflected in the high implied probability against a 2026 gathering.