U.S. Secretary of State Marco Rubio told a Senate committee that upcoming Ukraine peace talks will shift to a bilateral format between Russia and Ukraine, while warning that major gaps remain—especially over territorial claims in Donetsk. Rubio said security guarantees for Ukraine have broad agreement from the U.S. side, but acknowledged unresolved Russian positions and stressed that such guarantees would apply only after the war ends. He revealed recent trilateral talks involving the U.S., Russia and Ukraine were held in Abu Dhabi, with further discussions planned. Rubio also cast doubt on the effectiveness of European troops in Ukraine without a U.S. security backstop, as pressure mounts for Kyiv to negotiate.