突发！俄方：俄美未达成联合声明，会谈内容不公布

Group 1 - The core viewpoint of the article highlights the ongoing negotiations between Russia and the United States in Riyadh, which did not result in a joint statement due to Ukraine's stance [1][2][3] - The discussions lasted over 12 hours and were described as "difficult but constructive," indicating a willingness to continue dialogue in the future [1][3] - Russia's Foreign Minister Lavrov expressed support for restoring the Black Sea grain export agreement, emphasizing the need for guarantees from the U.S. regarding Ukraine's compliance [5] Group 2 - The article discusses the ongoing "fighting while talking" situation in the Russia-Ukraine conflict, where both sides are engaged in military actions while also participating in negotiations [8][11] - It notes a shift in battlefield strategies, with Russia aiming to weaken Ukraine's negotiating position through military pressure, particularly in the Kursk region [9][11] - Ukraine's counter-offensive towards the Belgorod border is seen as an attempt to create new leverage in negotiations, indicating a strategic approach to the ongoing conflict [11]