The two-day negotiations paved the way for further diplomacy, but fundamental differences remain, commentators say

Russia, Ukraine, and the US have concluded two days of negotiations in Abu Dhabi, reaching an agreement in principle on a major prisoner exchange. The first formal trilateral talks since February centered on wider European security arrangements, with Moscow reporting common ground on some issues and American negotiators also describing progress while acknowledging that the hardest questions remain unresolved.

US envoys Steve Witkoff and Jared Kushner are due to meet Russian President Vladimir Putin in Moscow on Thursday. Western European representatives were sidelined throughout the negotiations, although they reportedly held separate consultations with the American and Ukrainian teams.…