US Secretary of State Marco Rubio has cautioned against indefinite peace negotiations between Russia and Ukraine following their first direct talks in three years, held in Istanbul. The meeting led to a major prisoner swap and discussions on a future ceasefire. Rubio emphasized that while peace is crucial, Washington demands tangible results and won’t support open-ended talks. He also warned of new sanctions if no deal is reached. Meanwhile, Moscow insists that Ukraine’s NATO ambitions and military posture must be addressed to secure a lasting truce.